Question

— Susan, would you like to go hiking with us this afternoon?
— I'd love to, but I    study for a test.
A. may             B. have to         C. can

Answer 1

B

情态动词的考查。May意为“可以”；can意为“能够”，have to意为“不得不”，根据句意可知“我不得不为考试而学习”。