I learned that the eight parts of speech are nouns, pronouns, adjectives, verbs, adverbs, prepositions, conjunctions, and interjections. I also learned that articles are also important to complete a sentence.
For example, in the sentence "Greg hit Pete.", 'Greg' and 'Pete' are nouns while the word 'hit' is a verb. We can transform this sentence using pronouns by writing "He hit him." which means the same.