The book be Tom’s. Look! His name is on it.A. have toB. mightC. couldD. must

问题补充：

The book be Tom’s. Look! His name is on it.

A. have to

B. might

C. could

D. must

答案：

A. have to

B. might

C. could

(答案→)D. must

解析：have to必须，不得不；might可能；could能，能够；must必须，一定。句意：这本书一定是汤姆的。看！他的名字在上面。结合语境可知选D。