To improve his English,he spends _______ one hour a day listening to English programmes. [ ]

There are three floors ______ this building and my classroom is ______ the second floor.[ ]

May I _____ your bike?—Sure. But please give it back to me this afternoon.

They have to ______leaving for London because of the bad weather.

Bill Gates has created a wonderful “window” ______ people can surf the Internet freely．