Can you please check the sentences? Thank you, Writeacher.

1) Are there any questions before you start?
Did you have any difficulty in doing your homework?
2) Take a photocopy and pass the others on.
Share these copies, one between two.
Please, keep an eye on time.
3) Let's go/move on to the next exercise.
Let's recap on what we did the last time.
4)Please, discuss a topic of your choosing.

All look fine.

Certainly! Here are the revised sentences:

1) Are there any questions before we begin?
Did you encounter any difficulties while completing your homework?

2) Make a photocopy and hand the remaining copies to others.
Share these copies, with one for every two people.
Please ensure you monitor the time.

3) Let's proceed to the next exercise.
Let's review what we covered last time.

4) Please, choose a topic for discussion.