We can’t see the sun _____.[ ]
It is only when agriculture is fully developed___________industry can have abundant materials and markets.
Angela, I hear you are going to buy a new car.——Yes, but I can’t ________ an expensive one.
Does the child need any help? —-No. He is old enough to _____ himself.
Hello! Mrs. Smart! I want to talk _____ you _____ my daughter. [ ]