Question

When to use and how to use______important. Supply a verb.(is /are)

Answer 1

We have two noun phrases in the given sentence. They are separated by "and".

They are "When to use"  &   "how to use".

Since there are two noun phrases, we have to use the plural form of the verb. So the answer will be  "are".

Answer:     When to use and how to use are important.

Answer 2

Answer:

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