Using correct American English grammar takes years of practice in both reading and writing. Included in the category of grammar is the parts of speech. First, people learn the different parts of speech including nouns, verbs and adjectives. As they get older, they learn other parts of speech. Also, people then learn punctuation and when to use periods, exclamation points, question marks and commas. Along the path to learning English grammar, people will know which words to capitalize. Generally speaking, the beginning of each sentence and proper nouns are capitalized. After learning nouns and verbs, people need to make sure that their sentences contain subject verb agreement.