VOCABULARY AND USAGE

Hi friends, If we search any word in dictionary, it has many forms like noun , verb , adjective ,etc.

Do I need to memorize all the forms ?

While using it (spoken or written), How to make sure the word is appropriately used in that form that is noun or verb , etc ?

eg:: Menace- noun ; verb .

Please help me

You need to learn vocabulary in the context of sentences. You should be able to identify, in a sentence, the adjectives, nouns, verbs and adverbs. If you look up a word that you see in a sentence it would be good to recognize if it is one of the aforementioned parts of speech. By know what part of speech the word is, you will know which dictionary meaning(s) pertain to it.