Rules
Has is for...
He, she, it
Ana have been practicing ballet for 4 hours.
Ana has been practicing ballet for 4 hours.
You / talk / 20 minutes
You have been talking for 20 minutes.
The verb ends in...
-ing.
They have been ate only vegetables for the last 3 months.
They have been eating only vegetables for the last 3 months
We / learn this topic / last week
We have been learning this topic since last week
For is used with...
Periods of time
I have been studying for December.
I have been studying since December.
My dog / play / 30 minutes
My dog has been playing for 30 minutes
Since is used with...
Specific point in the past.
Camila and James have been dating since 7 months.
Camila and James have been dating for 7 months.
My siblings / argue / this morning
My siblings have been arguing since this morning