Adverbs of frequency

always, usually, regularly, normally, often, sometimes, occasionally, rarely, seldom, never are adverbs of frequency.

The position of these adverbs is:

before the main verb

		Adverb of frequency	Verb
I		always	get up	at 6.45.
Peter	can	usually	play	football on Sundays.
Mandy	has	sometimes	got	lots of homework.

after a form of to be am, are, is (was, were)

	Verb	Adverb of frequency
Susan	is	never	late.

The adverbs often, usually, sometimes and occasionally can go at the beginning of a sentence.
Sometimes I go swimming.
Often we surf the internet.

Somtimes these adverbs are put at the end of the sentence.
We read books occasionally.

http://www.englisch-hilfen.de/en/grammar/adverbien1.htm