Past Perfect Continuous образуется при помощи глагола to be в Past Perfect + Participle 1 . Past Perfect Continuous может обозначать действие, которое завершилось перед другим действием в прошлом.
– Although the sun was shining, it was still cold as it had been raining hard for two hours.
– He felt tired when he came home as he had been playing football.
Past Perfect Continuous также употребляется, чтобы показать, как долго что-либо происходило перед тем, как что-то еще случилось.
– She had been sleeping for two hours when we returned.
– It had been raining for an hour when I left home.
Past Perfect Continuous – это прошедшее время от Present Perfect Continuous.
How long have you been waiting?
He’s out of breath.
He has been running.
How long had you been waiting when the bus finally came?
He was out of breath.
He had been running.
Сравните формы Past Perfect Continuous и Past Continuous :
She had been sleeping for three hours when we returned. .
She was sleeping when we returned. .