It seemed as though the silence went on for a long time.
The silence went on, and the Mahdi did not move for a long time.
A long silence went by while they took it all in.
The silence went on so long that he grew concerned.
After the silence had gone on long enough, I finally got it.
The silence went on for what seemed like half an hour, but could not have been more than a couple of minutes.
The silence went on as the people around them talked.
I let the silence go on for a bit and then said: 'I'll tell you how far it had gone.
The silence had gone on for an awfully long time.
He wondered how long the silence was going to last.