The present perfect continuous tense, also known as the present perfect progressive tense, is used to describe actions that began in the past and have recently stopped, or actions that started in the past and are still continuing. The words “for” and “since” are often used with this tense.
subject + has/have been + v1 (ing)
AFFIRMATIVE FORM
Past actions which are still continuing
Example:
You have been waiting here for two hours (Still you are waiting).
I have been studying since this morning. (Still I am studying).
Past actions which have been recently stopped (There is usually a result now).
Example:
I’m tired because I have been running in the morning.
She is so tired because She has been dancing.
We use “for” to talk about a period of time:
Examples:
for two hours
for two weeks
for two months
We use “since” to talk about some point of time in the past:
Examples:
Since 6’o clock
Since Monday
Since last month
Since last week
Since 21st of March
Time's up
NEGATIVE FORM
subject + has/have + not + been + v1 (ing)
Example:
I have not been writing the letter / I haven’t been writing the letter.
You have not been playing cricket / You haven’t been playing cricket.
We have not been practicing / We haven’t been practicing.
She has not been studying / She hasn’t been studying.
He has not been teaching / He hasn’t been teaching.