1. Her face didn't show anything while he was saying this.
2. We continued to discuss the problem while they were having a smoke in the corridor.
3. While I was waiting for you,I looked through all these magazines.
4. It began to rain while he was sleeping in the garden.
5. He stopped her while she was entering the office.
6. We waited in the sitting-room while she was speaking to a friend over the telephone.
7. Everybody watched his face while he was playing the piano.
8. While I was eating my sandwiches at the station bar, two strangers came in.
9. While she was waiting for the bus, she read the newspaper.