The rule is that "three minute" is used as a compound adjective.
English grammar consists of the parts of speech (nouns, verbs, adverbs, ect.), spelling, punctuation, singular and plural nouns, subject and predicit understanding, and of course textbooks!
He, she, and it are pronouns, specifically third-person singular. The other nominative forms of pronouns are I, me, you, we, and they.
"Shelves" is the plural form of "shelf" because in English, regular plural nouns are often formed by adding an "s" or "es" to the singular noun. This is a common rule in English grammar for forming plurals.
"Each of you is" is the correct grammar. "Each" is a singular pronoun, so it should be paired with the singular verb "is."
Without consulting the Queen, standard English usage is "employees".
The word grammar is a common noun, a singular, abstract noun.
The article "a" is used before the word "useful" to indicate that it is a singular noun. In English grammar, "a" is an indefinite article used before singular nouns that begin with a consonant sound.
"Grammar" is an English equivalent of the French word grammaire. The French word serves as a feminine singular noun which may be preceded by the feminine singular definite article la ("the") or indefinite une ("a, an"). The pronunciation will be "gra-mehr" in French.
English grammar is more difficult to learn then rushian grammar?
Essentially, be English grammar dictates it. "Are" and "is" are both conjugations of the verb "to be." In the singular 2nd person (you) it is conjugated as "are." In the singular 3rd person (we) it is conjugated as "is." As for the historical origins of these words and why exactly they are what they are, you'd have too put a bit of research into it.
William Fewsmith has written: 'A grammar of the English language' -- subject(s): Grammar, English language 'A grammar of the English language' -- subject(s): Grammar, English language
Sidney Greenbaum has written: 'The Oxford English grammar' -- subject(s): Grammar, English language 'Verb-intensifier collocations in English' -- subject(s): Adverb, English language, Mathematical linguistics, Syntax, Verb 'A student's grammar of the English language' -- subject(s): Grammar, English language 'The Oxford Reference Grammar'