Concept:Knowing a word means understanding its correct usage in terms of grammar, context, and situation.
Explanation:Knowing a word is more than just spelling or writing it correctly.
It involves knowing how to use the word in grammatically correct sentences.
It also requires using the word in the appropriate context and at the right time.
For example, the same word can have different meanings in different situations.
Therefore, true knowledge of a word means knowing how, where, and when to use it.
Answer:Option A: how, where and when it is used.