Adverbs: Positions in the Sentence
Adverbs have three main positions in the sentence:
- Front (before the subject):
Now we will study adverbs.
- Middle (between the subject and the main verb):
We often study adverbs.
- End (after the verb or object):
We study adverbs carefully.
Source:  http://www.englishclub.com/grammar/adverbs.htm 

One of the hallmarks of adverbs is their ability to move around in a sentence. Adverbs of manner are particularly flexible in this regard.
Solemnly the minister addressed her congregation.
The minister solemnly addressed her congregation.
The minister addressed her congregation solemnly.
The following adverbs of frequency appear in various points in these sentences:
Before the main verb:                                               I neverget up before nine o'clock.
Between the auxiliary verb and the main verb:           I haverarelywritten to my brother without a good reason.
Before the verb used to:                                           I alwaysused to see him at his summer home.
Indefinite adverbs of time can appear either before the verb or between the auxiliary and the main verb:
He finallyshowed up for batting practice.
She hasrecentlyretired.