—Are you going to Guilin by plane?—It’s fast but expensive so I’m not sure. I take a tra

问题补充：

—Are you going to Guilin by plane?

—It’s fast but expensive, so I’m not sure. I take a train.

A. should

B. may

C. must

D. will

答案：

A. should

(答案→)B. may

C. must

D. will

解析：考查情态动词。should 应该，may 可能，must 必须，will 将要，句意：你打算乘飞机去桂林吗？很快但是比较贵，因此我不确信。我可能乘火车。所以选B。