What can you do to save electricity?

Question

1. I can turn off the lights when I leave my room.
2 I can turn off the lights when I don't use the room.
3.I can turn off the lights when I don't stay in the room.
4. I can turn off the lights of my classroom when we leave for the music room.
5. I can turn off the lights of my room when I go to school.

6. I can turn off the lights when I go to bed.
7. I can turn off the computer when I don't use it.
8. I can turn off the computer when I am not using it.
9. I can turn off the lights when I do other things.
10. I can turn off the lights when I study in my room.
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I have made sentences. Would you check them? Correct errors, please.

Answer 1

1 - 8 are fine.

9 would be better if you write this:
I can turn off the lights when I leave to do other things.

10 doesn't make sense ... unless you study in the dark!