Question: what are the three major components of grammar?
Answer: Parts of Speech. In English grammar, the eight major parts of speech are noun, pronoun, adjective, verb, adverb, preposition, conjunction, and interjection.
Nouns. The easy way to remember nouns is that they refer to people, places, or things. ... 
Pronouns. ... 
Adjectives. ... 
Verbs. ... 
Prepositions. ... 
Conjunctions. ... 
Interjections.