1. He stay up too late before an important meeting.

2. We turn off the lights when we leave the room.

3. You wear a helmet when riding a bike.

4. They listen to their teacher in class.

5. He visit his grandparents more often.

6. Students take notes during the lecture.

7. She call her parents and let them know she's safe.

8. they start preparing for the exam now?

9. he have called to let us know he was running late?

10. You have said those hurtful things to her; she's upset now.