Adverbs of frequency tell us how often something is done.

Adverbs of frequency include; always, constantly, continually, frequently, infrequently, intermittently, normally, occasionally, often, periodically, rarely, regularly, seldom, sometimes etc.

For example:

I always do my homework on time. - In this sentence always shows us the frequency (how often) I do my homework on time.
She goes out occasionally. - In this sentence occasionally shows us the frequency (how often) she goes out.

Most frequent always
nearly always
almost always
now and then
once in a while
hardly ever
scarcely ever
almost never
Least frequent never

Adverbs of frequency appear between the subject and the verb in a sentence:-

For example:

I always update the calendar at the beginning of the month.
Poetria often takes notes during the Skype sessions.

Adverbs of frequency appear after a form of the to be - am, are, is (was, were) in a sentence:-

For example:

I am never late.
Skype is occasionally frustrating.
They were always noisy.

Adverbs of frequency go between an auxiliary verb and the main verb:-

For example:

Anne doesn't usually smoke.

If there are two auxiliary verbs, the adverb of frequency goes between them:-

For example:

I have never been to Asia.

The adverbs of frequency often, usually, sometimes and occasionally can go at the beginning of a sentence:-

For example:

Usually I don't give personal advice. = I don't usually give personal advice.
Occasionally we go for a drive on a Sunday. = We occasionally go for a drive on a Sunday.

Adverbs of frequency go before the verbs used to or have to:-

For example:

I always used to celebrate bonfire night.
I usually have to get up early to walk Laika.

When something happens regularly at a fixed time we can use the following as adverbs:-

Every day
Every week = Weekly
Ever fortnight (two weeks) = Fortnightly
Every month = Monthly
Every year = Yearly/Annually

For example:

I get a newspaper every day. = I get the newspaper daily.
I pay my rent every month. = I pay my rent monthly.