ADVERB:

                                      It is a part of speech that modifies a verb, adjective, and other adverb.

  1.  As modifying a Verb

2. As modifying an Adjective      (He drives a very fast car. — How fast was his car?)
Some more examples:

3. As modifying another Adverb       

She walks very slowly. — How slowly did she walk?

Some more examples:

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