A dash is placed between the subject and the predicate. Placing a dash between the subject and the predicate: rules of the Russian language, two-part sentences, examples. Correct placement of the sign

A dash is placed between the subject and the predicate in the following cases:

When to use a dash

1. If the subject is expressed by a noun, a numeral in the nominative case, the predicate is also expressed by a noun or a numeral in the nominative case. And the copula is zero, that is, it is not expressed in the predicate, it indicates the present tense of the indicative mood. This can be checked by inserting “is” after the dash.

For example: Lesson duration - forty minutes. Maria Ivanovna - teacher. Twice two is four.

2. The subject is expressed by an infinitive, the predicate is expressed by a noun or numeral in the nominative case, or the subject is expressed by a noun or numeral in the nominative case, while the predicate is an infinitive, or both main members of the sentence are expressed by infinitives.

For example: Soaring above the ground is the privilege of birds. It is the duty of every citizen to abide by the laws of the country. Taking on everything means doing nothing.

3. The words “this”, “it is”, “means” (which is used in the meaning “this is”), “this means” are used when joining the predicate to the subject. A dash is placed before indicator words.

For example: Mom is the dearest person. Defending your homeland is the act of a hero. Freedom is a test of responsibility.

When you don't put a dash

However, there are exceptions to these cases. A dash is not placed between the subject and the predicate if:

1. The connective is not zero, most often expressed in words indicating time. For example: Sharik was a true friend.

With the predicate there are so-called comparative conjunctions, such as “as if”, “as if”, “exactly”, “as”, etc. For example: Eyes like emeralds. Dew is like a placer of diamonds.

There is a particle “not” before the predicate. For example: Brothers are not twins.

There is an introductory word between the subject and the predicate. For example: The introduction is just the beginning. The oasis seems like a mirage. Ivan Ivanovich is also a teacher.

Before the predicate there is an object that refers to it. For example: Andrey is my friend.

The predicate comes before the subject. For example: Outstanding comedian Yuri Nikulin.

The subject and predicate represent a stable phraseological turn. For example: Two boots in a pair.

2. In reverse word order, in the case when the subject and predicate are expressed by infinitives, or one of the main members of the sentence is an infinitive, and the second is a noun or numeral in the nominative case. There is no pause between them.

For example: This bliss to lie on the warm sand.

If there is a pause, then a dash is placed even if the word order is reversed.

For example: The highest art is to make the whole room laugh.

3. The word “means” is used in the sense of “therefore.”

For example: It became dark outside; This means that the day is approaching evening.

The word "means" is a verb in the following meanings:

Mean. For example: Hello in English means hello.

To testify to something. For example: Promising does not mean marrying.

Make a difference. For example: A mascot means a lot to a family.

The word “This” is used as the subject, which is expressed by a pronoun.

For example: This is classified information. It's a little expensive for us.

Need help with your studies?

Previous topic: Sentence structure: types according to the purpose of the statement and the emotional coloring
Next topic:   Minor members of the sentence: addition, circumstance, definition

Between the subject (subject group) and the predicate (predicate group), of all punctuation marks, only a dash is used. placed in place of the missing ligament.

Dash between subject and predicate PUT:

A dash is placed Examples
In the absence of a connective in a compound nominal predicate, if: a) both main members of the sentence are expressed by a noun in the I. p. The word is the commander of human power (V. Mayakovsky).

Love and friendship are a mutual echo: they give as much as they take (A. Herzen).

b) one of the main members is expressed by a noun in the nominative case, and the other by an infinitive, or both by an infinitive (in addition to the infinitive, the subject and predicate may include other words) The poet’s gift is to caress and scribble, a fatal stamp on him (S. Yesenin).

Shooting at stones means losing arrows (M. Gorky).

Drive out before evening and bring in

at dawn the herd is a great holiday for peasant boys (I. Turgenev).

c) the subject and predicate are expressed by numerals in I. p.; one main member is expressed by a numeral or numeral with a noun, and the other by a noun in I. p. Three times three is nine.

Four is an even number.

The specific gravity of pine is zero point six tons per cubic meter.

d) the predicate includes the words this, that means Language is a tool of thinking... To handle language somehow means to think somehow: inaccurately, approximately, incorrectly (A. Tolstoy).

Dash between subject and predicate NOT PUT:

There is no dash Examples
If:

a) before the nominal part of the predicate there is an introductory word, adverb, conjunction or particle (only, only, after all, unless)

The rook, of course, is a smart bird... (K. Paustovsky).

Mercury is also a metal.

March is just the beginning of spring.

b) the predicate includes comparative conjunctions as, as if, as if, exactly, that, anyway (what) A pond is like shiny steel (A. Fet). An unfinished book is like an unfinished journey (Proverb).
c) before the nominal part of the predicate there is a negation not, except in cases where both main members of the sentence (or one of them) are expressed by an infinitive Horses are not travel companions on foot (Proverb). Living life is not a field to cross (Proverb).

The main motive of my life is not to live my life in vain... (K. Tsiolkovsky).

d) between the subject and the predicate there is an addition, circumstance But this calmness is often a sign of great, albeit hidden strength (M. Lermontov).
e) the predicate is expressed by an adjective (full, short, comparative or superlative) The day is sunny.

The girl is smart and beautiful.

The weather is rainier in autumn, and people are more talkative in old age (I. Krylov).

f) the subject or predicate is expressed by a pronoun; She's a cunning girl. The book is mine.
g) the nominal part of the predicate, expressed by a noun, denotes the attribute of a certain person (there is no “break” intonation) My mother is a teacher.

His older brother is a good friend. Our friend is an elderly woman.

h) the predicate precedes the subject This valley is a wonderful place! (M. Leomontov)

Dash in an incomplete sentence

In incomplete sentences, a dash is usually placed when a predicate or other members of the sentence are omitted, if they are restored from the text of the sentence itself, most often complex: For several seconds, the shepherd boy and Metelitsa looked straight into each other's eyes: Metelitsa - with feigned indifference, the shepherd boy - with fear, sympathy and pity . (A. Fadeev) To the north of the city the Germans reached the Volga, to the south they were approaching it . (K. Simonov)

Punctuation marks are like markers. Who invented them and what is the role of these punctuation units besides another reason for lowering students’ grades for their incorrect placement in the dictation? But thanks to such elements of writing, the perception of the text and the emotional message are achieved. It is simply necessary to be a literate person today. Therefore, knowledge of basic punctuation and spelling norms is necessary for everyone. The dash between the subject and the predicate - examples, exceptions, rules will be discussed in this article.

Semantic centers of sentences (SSC)

Having initially read the title of this publication, a person who has graduated from school a long time ago most likely begins to frantically remember the members of the sentence. And it’s unlikely that examples of sentences with a dash between the subject and predicate immediately come to mind.

A combination of words connected in meaning and having intonation completeness is called a sentence, the totality of which forms the text. Each such statement tells about some object or subject. By asking questions inherent in the nominative case - “what?”, “who?” - you can determine the first component of the grammatical basis of the statement - the subject. That is, it is part of the semantic center of the sentence. “Employees at the repair shop have completed preparing the equipment for winter.” In this version, “employees” are the subject of the message. We are talking about repair shop workers.

Having decided who the sentence is about, it is necessary to highlight the action performed by the subject of the statement. It is expressed by the predicate. A logical question arises in the example under consideration - “What did the employees do?” - completed the preparation of the equipment. The predicate is “completed” and is considered the second semantic center of the sentence.

Dash function

The sign defining silence, semantic separation, was introduced into Russian writing by the historian N. M. Karamzin. Although there is an opinion that the punctuation unit first appeared in the Russian press in the 60s, and Nikolai Mikhailovich only contributed to its popularization.

In modern Russian writing, a dash between the subject and the predicate is a punctuation rule that every fifth grader knows. Main purpose of the sign:

  • Separating function. Separating parts of a statement with meaning and filling in the excluded members of a sentence with a sign. I walked along the poppy field to the left, and Andrey went to the right. Here the predicate “went” is missing in the second part of the statement. The dividing function is the dash between the subject and the predicate. Examples: Kyiv is the capital of Ukraine, the meeting place is the assembly hall. In the first case, Kyiv is the subject, and the capital is the predicate. Both parts of the sentence are expressed by a noun. This is one of the requirements when a dash is placed between the subject and the predicate.
  • Excretory function. Writing lines in dialogue.
  • Connective purpose: to quantitatively or semantically combine two words. Bus "Moscow - Dolgoprudny".

Punctuation: a dash between the subject and the predicate. Explanation with examples

When the semantic centers of a statement are nouns, moreover, in the nominative form, there are several cases in which the sign of “silence” is used:

  1. To convey a fixed (logical) meaning: A square is a regular quadrilateral. Algebra is a discipline that generalizes and expands knowledge of arithmetic.
  2. Journalistic statements or scientific judgments that describe the characteristics of an object or evaluate a phenomenon: A thunderstorm is a natural phenomenon that occurs as a result of electrical discharges.
  3. Judgments where the subject and predicate are identical in meaning: Sevastopol is a city in Crimea.
  4. After subjects answering one question and referring to one predicate: Kirovograd, Dnepropetrovsk, Vinnitsa are cities in the central part of Ukraine.
  5. To add precision to a statement: Mom is my friend. Or when in judgments there is a connective like “this”, “here”: The path through the dunes is desolate kilometers of silence, drought and thirst.

Requirements for placing a dash when the centers of a sentence consist of different parts of speech

The “-” sign can be used in statements where the main members are not only nouns.

So, we continue to consider the dash between the subject and the predicate. Examples of sentences when semantic centers are expressed by different parts of speech:

  1. Five six is ​​thirty. The phrase “five six” is the subject, “thirty” is the predicate, both are expressed by a numeral. The height of the peak of the Carpathians is two thousand six hundred fifty-five meters. In this case, “height” is a noun that reflects the subject; after the sign, the entire phrase refers to a numeral and is expressed by a predicate. It follows: a dash is placed when the main members of the statement act as a numeral and/or a noun. But! In the nominative case. The exception is texts describing the characteristics of the subject in specialized literature, for example: boom reach 12 meters; The melting point of the metal is 1000 degrees.
  2. To live with wolves is to howl like a wolf. SVPs refer to the indefinite form of the verb (IFV). Conclusion: sentences with a dash between the subject and the predicate can be found when its main members are expressed by the infinitive.
  3. Our goal is to complete the task before Monday. The combination of an infinitive and a noun expressing SCP also requires the use of a “-” sign.

Cases when the sign is not used

  • The absence of a dash between the subject and the predicate is possible when SCPs are made up of simple sentences, usually in a conversational style: m oh dad director of a scientific enterprise; my sister is an analyst.
  • If the predicate is attached to the second part of the grammatical basis of the statement (the subject) with the conjunctions “as”, “as if”, “sort of like”, “exactly”, “as if”: m oh the school yard is like a garden; the stars are like little diamonds; the sky is like an ocean.
  • The predicate expresses negation using the particle “not” - this is the case of the absence of a dash between the subject and the predicate. The rule has exceptions, but more on them later. Examples: The heart is not a stone. The word is not a sparrow.
  • The grammatical basis of the sentence is divided by an introductory word: a August is known to be the season for fruits and vegetables; Ivanov is now a famous hairdresser. If in the last version we omit the adverb “now”, then we get a statement when a dash is placed between the subject and the predicate: Ivanov is a famous hairdresser.
  • The semantic centers of the sentence form a phraseological turn: d a pair of boots.
  • The predicate appears in a sentence before the subject: з wonderful girl Tatyana Pavlovna.
  • The subject is a personal pronoun, and the predicate is a noun. He is an ulcer, he is a plague, he is a corruption of these places.

Exceptions

Deviation from the requirements put forward for the placement of a dash or its absence can be observed in modern authors and classics. For example, the judgment: uh that man is like a hero! It seems that according to the punctuation rule, if there is a connective “how”, then the “-” sign is not placed. However, its presence can be justified by the author’s desire to emphasize the nuance of the comparison.

For a clear contrast, the author can use intonation and logical stress. In this case, a dash is placed between the subject and the predicate. Examples: His views on raising children - isn't this a prejudice? Preparing for the Olympics is not that easy.

Dash between subject and predicate: table

There is a dash (subject + predicate):

Noun + noun

A dog is man's friend.

Numeral + numeral

Three times two is six.

Infinitive + infinitive

Eating right means loving yourself.

Infinitive + noun

Drinking coffee in the morning is a pleasure.

Noun + infinitive

My goal is to defend my diploma.

Subject (that means this) predicate

Teaching is the best hobby.

No dash:

"Not" predicate

The word is not a sparrow.

Predicate (precisely, sort of like, as if, as) subject

Lips like rose petals.

Predicate + subject

A wonderful person Andrey Vladimirovich!

Subject = pronoun

She's a librarian.

Preparing for the Olympics is not that easy.

Conclusion

The basic rule before placing a dash is to determine the semantic center of the sentence (subject, predicate), establish which part of speech they belong to, and know the cases when such a sign is absent.

Competent language skills are the key to prosperity, success and respect. After all, life is an endless exam.

§10

Between the subject and the nominal predicate in place of the missing connective a dash is added, if the subject and predicate are expressed as nouns in the nominative case: The outbuilding near the house on Sadovaya, designed by Mikhail Aleksandrovich Vrubel, is the only building from the Mamontovs’ possessions that has almost preserved its appearance to this day(Keys); Pushkinsky region - the land of stones(Gaych.); This portrait is the only picturesque image of the daughter of Anna Petrovna Kern(Gaych.); ...My ability to keep the past to myself is a hereditary trait(Eb.); And the woman leaning over the fence is your second cousin(Shcherb.).

§11

A dash is placed before the predicate, attached to the subject by words here it is: “Respect for the past -that's the line “that distinguishes education from savagery,” Pushkin once said(Spread); Pushkinogorye -this is not only a monument historical and literary,This and a peculiar botanical and zoologicalgarden , a wonderful natural monument(Gaych.). As a link, a combination is also possible it is: Hypotenuse -this is the side right triangle, opposite the right angle(from the textbook).

§12

A dash is placed when expressing both the subject and the predicate (or only the subject, or only the predicate) with an infinitive: In this cityknow three languages ​​are an unnecessary luxury(Ch.); An incomparable feeling -hear their[rooks] for the first time after six months of winter death!(Boon.). The presence of negation does not remove the sign: Tea drink - not firewoodchop (last); Lifelive - not a fieldgo (last). The same if the predicate contains words this means: Wait for permission -Means waste time(gas.); Leave the institute now -this means lose everything(gas.); And to understand a person -Means already sympathize with him(Shuksh.).

§13

A dash is placed between the subject and the predicate, if they are expressed by numerals (or a phrase with a numeral), and also if one of the main members of the sentence is expressed by a numeral: So, nine forty -three hundred sixty , So?(Peace); The depth there from the boat isfour flywheels , that is six meters(Shol.).

If the particle is used not before the predicate-numeral (cf. the same when expressing the predicate as a noun, § 15, paragraph 3), the dash is not placed: A man can, for example, say that twice is twonot four , and five or three and a half; and the woman will say that twice is two - a stearin candle(T.).

§14

A dash is placed with a predicate expressed by a phraseological turn: Pie -you'll lick your fingers ; He has talent -God bless everyone ; The mother shed tears of joy, and the father -at least something! (Cool.); Hut -so-so , barn(Shuksh.); Efim himself -don't put your finger in your mouth (Shuksh.); And Victor -neither father nor mother (Cool.); Night -at least poke out your eyes! (A. Color.).

The presence of the particle not, as well as introductory words for stable combinations in the role of a predicate, prevents the placement of a dash (but does not prohibit): This officerno match for you , Mister Gendarme(Fed.); We have him as a scientist, and plays the violin, and cuts out various things,in a word, a jack of all trades (Ch.).

§15

Dash between subject and nominal predicate not placed:

1. If the subject is expressed by a personal or demonstrative pronoun: She his daughter. He wants to understand her(Shcherb.); This cabinet? This bedroom?(Ch.)

2. If one of the main members is expressed by an interrogative pronoun, and the other by a noun or personal pronoun: Who your defender?What is studying?Who she?

3. If the predicate noun has a negation: Scenery not an appendage to prose and not a decoration (Paust.); Russianot St. Petersburg , she's huge(Priv.); Old agenot joy (last). However, when contrasting a predicate with a negation, it requires a dash (not... a): And at the same time he noticed that he was not the master in his house, but only an integral part of it(M. G.) (cf. without contrast: He is not the master of his house).

4. If the predicate is expressed by an adjective or participle: And your roomso good for a child(Ch.); I have a lot of good people, almost all of themgood (Sim.); He had two wounds. Woundseasy , but the man lost a lot of blood(Paust.); Log housepink, peeling, small, rustic, covered with a green iron roof (Kav.); harsh autumnsad late view(Sick.); There's a feast in the dining room hot Andardent (Sick.).

However, with a predicate-adjective, a dash is placed when there is structural parallelism of parts of the sentence, accompanied in oral speech by intonation emphasis (emphasis) on both members of the sentence: Everything in her appearance attracted attention: sight -spicy , hairstyle -boyish , cloth -modern, fashionable ; Wed with emphasis on only the predicate: Weatherobnoxious , roadnasty , coachmanstubborn , the horses don't carry, and the caretaker is to blame(P.). A dash is also possible in the presence of several (homogeneous) predicates: Her son isyellow, long and with glasses (M.G.).

5. If the predicate is expressed in a phrase with comparative particles like, as if, what, exactly, sort of like etc.: Lifelike a legend ; Skylike a pitched tent ; Broochkind of like a bee (Ch.); Forestexactly a fairy tale ; Weekthat one day . Passes quickly; Pondlike shiny steel (Fet). A dash is not placed when introducing a predicate that lexically coincides with the subject: Ice like ice, desertlike deserts (Kav.); Villagelike a village ; Houselike a house - old, dark(Shuksh.).

6. If between the subject and the predicate noun there is an introductory word, circumstance or addition, as well as a conjunction or particle: Rook,Certainly , the bird is smart and independent, but he has no voice(Paust.); My fatherfor me friend and mentor; MoscowNow port of five seas; My brotherSame engineer; This stream only beginning of the river.

Dash in an incomplete sentence

§16

In incomplete sentences, in place of missing sentence members or parts thereof a dash is added.

1. In parts of a complex sentence with a parallel structure, as well as in a simple sentence with homogeneous repeating members of the sentence, where the missing member is restored from the first part of the sentence: It was getting dark, and the clouds were either parting or setting in from three sides: on the left - almost black, with blue gaps, on the right - gray, rumbling with a continuous roar, and from the west, from behind the Khvoshchina estate, from behind the slopes above the river valley , - dull blue, in dusty streaks of rain(Boon.); For him, one story inevitably evokes another, and that one - a third, and a third - a fourth, and therefore there is no end to his stories(Paust.); Some consider the portrait to be the work of Van Dyck, others - Rembrandt(Paust.); So she lives alone. Walks around the garden during the day, around the house at night(Shcherb.).

2. In a simple sentence with a missing predicate indicating the direction of movement: Tatiana goes into the forest, the bear follows her(P.).

3. If the missing member of a sentence is restored from previous sentences: - Do you like green onion pies? I am like passion!(M.G.); In another room, a jeweler's workshop has been recreated. In the third there is a shepherd's hut, with all the shepherd's utensils. In the fourth there is an ordinary water mill. In the fifth - the setting of a hut where shepherds make cheese(Sol.).

§17

A dash is placed in sentences consisting of two components with the meaning of subject, object, circumstance (in different combinations) and constructed according to the following schemes: “who - to whom”, “who - where”, “what - to whom”, “what - where”, “what - how”, “what - where”, “what - for what” etc.: Teachers to schoolchildren; Journalists are in hot spots; Literary awards - to veterans; Textbooks - for children; All wells are operational; Grades are for knowledge. The dash is preserved even when the parts are rearranged: You have the key to the university.

Such proposals are common in newspaper headlines.

§18

In independently used sentences with a missing predicate that cannot be restored from the context, it can be put dash. Such sentences are divided by a pause into two components - adverbial and subject: Behind bars - a fabulous bird(Sick.); In the village lanes there is knee-deep mud(Shuksh.); Above the yellow straw fields, above the stubble - blue sky and white clouds(Sol.); Behind the highway there is a birch forest(Boon.); There are clouds all over the sky(Pan.); There is low hanging dust over the square(Shol.); Behind the screen is a door leading to the stairs(Eb.).

However, in the absence of a pause and logical emphasis on the adverbial part of the sentence, a dash not placed: There, on unknown paths, are traces of unprecedented animals.(P.). The same when expressing subjective-adverbial meaning: There is excitement in the audience; There is sadness in my soul.

Dash in join function

§19

A dash is placed between two (or more) words that, when combined with each other, mean limits (meaning "from... to") - spatial, temporal, quantitative: Trains with signs “Moscow - Kara-Bugaz , throughTashkent - Krasnovodsk » (Paust.); Mistakenly believing that horse chestnut culture in northwestern parks is not a phenomenonXVIII-XIX centuries, and later, all chestnuts were removed from the Trigorsk and from the burial hill of the Svyatogorsk monastery(Gaych.); Oil reserves at Cheleken are very small and should be exhausted within the firstten - fifteen years of production(Paust.). The same when denoting quantities with numbers: Manuscript of 10-15 author's sheets(see also the spelling of combinations indicating an approximate quantity: Spelling, § 118, paragraph 5 and § 154, paragraph 4.)

§20

A dash is placed between two (or more) proper names, the totality of which is called a doctrine, phenomenon, etc.: lawBoyle - Mariotta ; matchKasparov - Karpov .

A dash is also placed between common nouns, the combination of which performs a defining function for a noun: Systemman - machine ; Relationshipteacher - student ; Problemmarket relations - social justice . The number of combined names can be more than two: Problemproduction - man - nature ; Article by V. A. Sukhomlinsky“Teacher - team - personality” .

Dash in highlight function

§21

A dash is placed before the members of the sentence to emphasize them, accentuate them (for stylistic purposes). Such members of a sentence are called connecting members.

1. A dash is placed to emphasize, accentuate explanatory parts of the sentence located at the end of the sentence. Most often this circumstance: This is very bad, as I had to write -for a piece of bread (Boon.); ...And again the rickshaw wandered down the street -this time to the hotel (Boon.); The next day the seminarians again clashed with the cadets -open, near the Summer Garden (Kav.); Throughout the spring, Nikolai met with Ovrazhny only once -by chance, on the street (Shol.). Such a dash can be replaced by a dot (see § 9).

2. A dash can be placed for stylistic purposes after coordinating conjunctions or combining them with particles: Death took off his worn-out bast shoes, lay down on a stone and fell asleep(M.G.); And here is the river(Cool.); I have papers... but they are no good(G.).

§22

A dash is placed to emphasize opposing members of a sentence: It’s scary, sweet, inevitable, / I need to throw myself into the foamy shaft, / You, a green-eyed naiad, / Sing and splash around the Irish rocks(Bl.).

1. A dash is placed between the subject and the predicate in the absence connectives, if both main members of the sentence are expressed nouns in the nominative case,

For example: Moscow is the capital of Russia. The gathering place is the parade ground (Sholokhov).

As a rule, a dash is placed:

1) in sentences that have the nature of a logical definition ,

For example: Geology is the science of the structure, composition, history of the earth’s crust;
2) in sentences of a scientific or journalistic style containing a characteristic, assessment of an object or phenomenon,

For example: Life is a special form of movement of matter that arises at a certain stage of its development;
3) after homogeneous subjects,

For example: Flattery and cowardice are the worst vices (Turgenev); Space and time are the basic forms of all existence;
4) to clarify the meaning of a sentence;

compare: The elder brother is my teacher; My elder brother is a teacher.

A dash is usually not placed, although the subject and predicate are expressed in the nominative case of the noun:

A) in simple sentences of conversational style of speech,

For example: My sister is a student;

b) if there are comparative conjunctions between the subject and the predicate as if, as if, exactly, all the same, all the same, kind of like etc.,

For example: Pond like shiny steel (Fet); You are like a white dove among sisters among gray, simple pigeons (Nekrasov); Your brooch looks like a bee (Chekhov); The houses of the city are like piles of dirty snow (Gorky).

Deviations from this rule are associated with the author’s desire to emphasize the connotation of comparison contained in the predicate,

For example: Silence is like a piece of ice, you can break it further with a whisper (Leonov); Your speeches are like a sharp knife... (Lermontov); ...Such a phrase is like a grand helmet in a jumbled mess (Turgenev);

V) if the predicate is preceded by a negation Not,

For example: This officer is no match for you... (Fedin); Analogy is not proof. Compare proverbs and sayings: The word is not a sparrow: if it flies out, you won’t catch it; Poverty is not a vice; The heart is not a stone.

But a dash is placed if it aims to logically and intonationally emphasize the predicate,

For example: But an explanation is not an excuse (Gorky); “Human blood is not water” (Stelmakh); Living life is not a field to cross (proverb);

G) if between the subject and the predicate there is an introductory word, adverb, conjunction, particle,

For example: ...The goose is known to be an important and sensible bird (Turgenev).

Compare the presence or absence of a dash depending on the specified conditions:

Cotton is the most important industrial crop. – Cotton, as is known, is the most important industrial crop (an introductory combination has been inserted).
Cinema is the most popular art form. – Cinema is still the most popular form of art (adverb inserted).
Kok-sagyz is a rubber plant. – Kok-sagyz is also a rubber planter (a conjunction is inserted).
December is the beginning of winter. – December is just the beginning of winter (particle inserted);

d) if the predicate is preceded by an inconsistent minor member related to itoffers,

For example: Stepan is our neighbor... (Sholokhov);

e) if the predicate precedes the subject,

For example: A wonderful person, Ivan Ivanovich! (Gogol).

The placement of a dash in this case emphasizes the intonational division of the sentence into two compounds,

For example: Nice people are my neighbors! (Nekrasov); The good side is Siberia! (Bitter); Psychological curiosity - my mother (Chekhov);

b) if the subject in combination with the predicate forms an indecomposable phraseological phrase,

For example: A theory that fixes only patterns is worthless (S. Golubov).

2. A dash is placed between the subject and the predicate if both of them are expressed by the indefinite form of the verb or if one of the main members of the sentence is expressed by the nominative case of the noun, and the other by the indefinite form of the verb.

For example: To teach a scientist is only to spoil him (proverb); Our duty is to defend the fortress until our last breath... (Pushkin).

3. A dash is placed before the words this, this is, this means, this means, adding the predicate to the subject.

For example: The Kremlin is a treasury of Russian architecture, the creation of great masters, a living chronicle of centuries-old history (From newspapers). All the past, present and future are us, and not the blind force of the elements (Gorky).

Compare: The latest autumn is when the mountain ash shrivels from frost and becomes, as they say, “sweet” (Prishvin)(the whole sentence acts as the predicate).

4. A dash is placed if both main members of the sentence are expressed by the nominative case of a cardinal numeral or if one of them is expressed by the nominative case of a noun, and the other by a numeral or a phrase with a numeral.

For example: So, nine forty is three hundred and sixty, right? (Pisemsky); Ursa Major - seven bright stars; The specific gravity of gold is 19.3 g/cm3.

In specialized literature, when characterizing an object, a dash is often not placed in this case, for example, the melting point of gold is 1064.4?; The crane's lifting capacity is 2.5 tons, boom clearance is 5 m.

5. A dash is placed between the subject, expressed by the infinitive form of the verb, and the predicate, expressed by the predicative adverb ending in -o, if there is a pause between the main members of the sentence,

For example: Preparing for exams is not so easy (Fedin); Giving in is shameful (V. Tendryakov); It’s very unbearable to move (Goncharov).
But (in the absence of a pause): It is very easy to judge a person in disgrace (L. Tolstoy).

6. A dash is placed before the predicate, expressed phraseological phrase,

For example: Both a woman and a man are a pair of nickels (Chekhov); And the porch - God forbid another prince... (A.N. Tolstoy).

7. With a subject expressed by the pronoun this, a dash is placed or not depending on the logical selection of the subject and the presence or absence of a pause after it.

Compare:
A) This is the beginning of all beginnings; This is the actress's first performance; This is loneliness (Chekhov);
b) This is the house of Zverkov (Gogol); This is a net for catching quails (Chekhov); This is a very difficult problem.

8. A dash is usually not placed if the subject is expressed by a personal pronoun and the predicate by the nominative case of the noun,

For example: ...I am an honest person and never give compliments (Chekhov); I am terribly glad that you are my brother (L. Tolstoy); He is corruption, he is the plague, he is the plague of these places (Krylov).

In this case, a dash is placed when contrasting or when logically emphasizing the predicate,

For example: You are an old child, a theorist, and I am a young old man and a practitioner... (Chekhov); I am a manufacturer, you are a shipowner... (Gorky); Not I, not I, but you are the harmful element (Fedin).

9. A dash is not placed if one of the main members of the sentence is expressed by an interrogative-relative pronoun, and the other by a noun in the nominative case or a personal pronoun,

For example: Tell me who your friend is and I will tell you who you are.

10. As a rule, a dash is not placed if the predicate is expressed by an adjective, pronominal adjective, or prepositional-nominal combination.

For example: She has a very kind heart, but a bad head (Turgenev); My cherry orchard! (Chekhov). The shark’s back is dark blue, and its belly is dazzling white (Goncharov).

Placing a dash in these cases aims to break down the sentence intonationally and facilitate the perception of its content,

For example: The pupils are cat-like, long... (Sholokhov); The height near the scattered houses of the farm is commanding... (Kazakevich).

11. In footnotes, a dash separates the word being explained from the explanation, regardless of the form of expression of the predicate.

For example: Lakshmi is the goddess of beauty and wealth in Indian mythology; Apis is considered a sacred animal by the ancient Egyptians.