The conference has been held to discuss the effects of tourism ______the wildlife in the area.A. in B on C. at D. with
The teacher told us that light ______ faster than sound.
If better use is ______ of your spare time, you will make still greater progress in it.
This is her only request that the room ______ after being used.
— I don’t know ______ Mr. Green will come to see us. — He will help us with our English.
—I apologize to you for my rudeness yesterday, Mary? —Never mind, and I think ______ of it.