:
1 He was tired because he had been running.
2 My mum was angry because I had been watching TV all afternoon.
3 My friends had been playing football for hours when I arrived.
4 We had been waiting for the concert to start for half an hour, when they made the announcement.
5 My sister had been learning French for six years before she went to France.
6 We had been swimming for about an hour when it started to rain.