Answer:
Adverb of how refers to an adverb that qualifies the manner in which something is done.
Adverb of when refers to an adverb which tells when and how frequently an action is carried out.
Explanation:
Adverb refers to a word or phrase which qualifies or modifies a verb, an adjective, etc.
<u>Adverb of how</u>
Adverb of how refers to an adverb that qualifies the manner in which something is done. An example of adverb of how is given as follows:
John is walking <u><em>slowly</em></u>.
In the example above, <em><u>slowly</u></em> is an adverb which qualifies the manner in which John is walking.
<u>Adverb of when</u>
Adverb of when refers to an adverb which tells when and how frequently an action is carried out. An example of adverb of when is given as follows:
David <u><em>always</em></u> reads in my room.
In the example above, <em>always</em> is an adverb which tells us how frequently David reads in his room.