_______ is this backpack?—It’s yellow.[ ]

Have you cooked for your parents?—Yes, of course.

Do you have the new iPad? —Sorry, they have been______. You may come next week.

They will try their best in the Dragon Boat Racing _______ they may fail.

I had just got up and was about to cook my breakfast ___the telephone rang loudly, but it hung up __I could answer it .