There is ______ “u” and ______ “s” in the word “bus”.

Which one do you want to buy, an iPod touch 4, an iPad 3 or an iPhone 5?—______. They are too expensive.

Did your classmates have a good time in the Disneyland last weekend?—Yes. They enjoyed _________ very much.

What do you like to do _____ such a windy day?..[ ]

Robert is away. He _______ America since last week.