Different parts of the English language form the basis for excellent writing and speaking. These are known as Parts of Speech.
Some of these are nouns, verbs and articles.
The dictionary is helpful in telling what part of the sentence structure the word may be used for. If a word names a thing, that word has a function or use in English grammar as a noun. A word that means an action is a verb. As well, however, some individual words can be used as both nouns and verbs. Then the student must understand exactly what is needed in the sentence.