Past perfect simple vs past perfect continuous 3 - tutto inglese - Imparare l'inglese gratis on line

They (sleep) for just a few hours when the alarm went off.
I (read) reports all evening when I finally understood the error.
He (send) the invitation before he received the confirmation.
She (bake) all afternoon when guests arrived unexpectedly.
They (study) the material before the test was postponed.
We (work) together for several years when we decided to start our own business.
He (clean) the garage before his parents visited.
She (sing) in the choir for several years when she was selected for a solo part.
They (finish) the marathon when they realized they were filmed for a documentary.
I (wait) at the clinic for over two hours when the doctor finally saw me.