Don't to turn off the lights when you leave the classroom,Tom.
All right,Ms.Lee.
It's still raining.We'd better keep (wait)for a while.
The woman looked at the young man (angry)and didn't say a word.
The keeper tells the visitors (not touch)the tigers.It's very dangerous.
The Smiths live on the (nine)floor of the spartment.
Smoking is to our health.( harm )