1. We have known each other since we were children.
2. The children has been playing computer games for two hours.
3. Have your sister had that hairstyle for a long time?
4. l have loved her since the first day we met.
5. My internet connection has not worked since yesterday.
6. How long have you been waiting?.
7. I have been a teacher for three years.
8. It has been snowing since five o'clock this morning.
9. Sam has not studied enough since recently.
10. Have you been living in London for a long time?