An adverb is a describing word. It describes a verb, another adverb, or an adjective. Adverbs answer the how, where, when, and to what extent questions. Many adverbs end with -ly. Examples are happily, slowly, loudly, and soon.
Punctuation marks help make the meanings of sentences clear.
The period is used at the end of a declarative sentence and a command. Mother baked chocolate chip cookies. Go to your room. A period is used at the end of an abbreviation. Oct. Mr. Dr. A.M. Ms. Use To, Too, and Two To, too, and two are pronounced the same way but have different meanings.