---Can I pass the exam this time Mr.Li?---I don’t think you can you work hard.A. unlessB.

问题补充：

---Can I pass the exam this time，Mr.Li?

---I don’t think you can you work hard.

A. unless

B. until

C. if

D. when

答案：

(答案→)A. unless

B. until

C. if

D. when

解析：A.unless 除非，B.until直到，C.if如果，D.when当…时候，句意：--这次我能通过考试吗，李先生？--我想你不能除非你努力。选A。