What ________ useful book ! —Yes, it is. But I found___________ difficult for me to read.

Will you come to the dinner party?—I won’t come unless Jenny ___________。

A: Listen! Is it Linda singing in the next room? B: No, it __________ be her. She is still in Shanghai.

I like red best. What about___________?—My favourite colour is orange. It represents joy.

People who eat a balanced diet should be healthier than _____ only eat biscuits.