Present Perfect Continuous – How long

teaching English

We use the present perfect continuous when an action started in the past and is continuing.

I’ve been teaching English for 15 years.

Look at the construction:

Subject to have been -ing form of verb
I have been living abroad for 20 years.
They have been going out together for 3 years.
She has been studying English since she was a child.

For and Since

For + a number Since + a date or time
for 3 weeks
for 8 days
for 20 hours
since Tuesday
since 1990
since I was born

We say for + a number

Examples

She’s been working for three weeks.
He’s been sleeping for eight hours.
I’ve been waiting for two hours.

We say since + a date or time

Examples

She’s been here since Tuesday.
He’s been doing this job since 2000.
I’ve been playing football since I was 5.