Ответ:
We have been bulding his house since 1994.
Where are you? I have been waiting you for an hour already.
He has been working hard since four o'clock.
Kate has been washing the floor for twenty minutes already.
How long have you been learning the French language?
The children have been playing football since three o'clock but they are not tired.
I haven't been eating at nigjt for two years.
Can you see my glasses? I have been looking for them for ten minutes but I have not found them yet.