Adverbs of frequency

You use adverbs of frequency to say how often you do something. The most common ones are:
never, seldom, rarely, occasionally, sometimes, frequently, often, usually, normally, always.

Adverbs of frequency usually appear between the subject and the verb.
We usually eat out on Friday evenings.

With the verb be the adverb of frequency appears after the verb.
I am sometimes late for my classes.

Occasionally, sometimes, frequently often, usually and normally can also appear at the beginning or end of sentences. When they appear at the beginning of a sentence we want to emphasise the frequency:
Occasionally she works until seven o'clock in the evening.

Never, seldom, rarely and always are not normally used at the beginning or end of sentences.