问题补充：
It is difficult, so I suggest that you it to an expert.
A. should leave
B. will leave
C. are leaving
D. may leave
答案：
(答案→)A. should leave
B. will leave
C. are leaving
D. may leave
解析：考查虚拟语气。suggest 后跟宾语从句应用虚拟语气，其结构为should +动词原形，should 可以省略。所以选A 。
