Have you been to the Great Wall?－Perhaps not in my memory. _______ , it might have been during my early childhood.

Tom is expecting a pet for long, but his daddy has no time to buy _________ for him.

I can’t find ________ beef in the fridge. Shall I buy some?

The children won’t go out flying kites if it __________ tomorrow.[ ]

I __________ this book for two weeks. I have to return it now.