Adverbs are used to describe actions. They may come before or after a verb, but not between a verb and its object.

Mrs.Jenner sang softly. (Most common word order.)
Mrs. Jenner softly sang. (Also possible.)

Mrs. Jenner softly sang a lullaby.

Mrs. Jenner sang a lullaby softly.

Mrs. Jenner sang softly a lullaby. (Not correct.)

Adverbs may come between a main verb and its auxiliaries.

Mrs. Jenner is softly singing a lullaby.
Mrs. Jenner softly is singing a lullaby. (Not correct.)

Mrs. Jenner has been softly singing that lullaby for a long time.

Some time and frequency adverbs are "movable." That is, they can be placed at various points in a sentence.

Yesterday I visited the dentist.
I visited the dentist yesterday.

Jack Prompt is here already.

Jack Prompt is already here.

Caution:
Even though some adverbs can be used in certain sentence positions, others can not.

I yesterday visited the dentist. (Not okay.)
I already visited the dentist. (Okay.)

Already I visited the dentist. (Not okay.)

Adverbs such as quite, very, really, extremely, and absolutely are used to modify adjectives and other adverbs.

They come directly before the words they describe.

Greg is quite happy with his new boss.

Sue eats very slowly.

You're absolutely right!

Many adverbs can be formed by adding "ly" to adjectives:

Carl is a quick runner.
Carl runs quickly.

Some adverbs are identical to adjectives in form. Others are completely different.

Carl is a fast runner. (Adjective)
Carl runs fast. (Adverb)
Jill is a good student. (Adjective)
Jill studies well. (Adverb)

Be careful with words like hardly and lately, which have no relation to the adjectives/adverbs hard and late.

Jacob kicked the ball hard.
Jacob hardly kicked the ball.

Trudy came to class late.

Trudy hasn't come to class lately.
He kicked the ball with tremendous force.)
(He barely touched the ball.)

(She was tardy.)

(She hasn't been to class recently.)

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