1. My friend (to ask) when the dean entered the classroom. 2. A new grammar rule (to explain) by the teacher now. 3. I think we (to follow). 4. We received the telegram when the letter (to type). 5. While the experiment (to carry out), nobody left the laboratory.
2. A new grammar rule (to explain) by the teacher now.
3. I think we (to follow).
4. We received the telegram when the letter (to type).
5. While the experiment (to carry out), nobody left the laboratory.