Question

It is difficult for us to learn a lesson in life ____we’ve actually had that lesson.

A.until    B.after    C.since    D.when

Answer 1

A

解析:

A。由语境逻辑可知，人的一生难以吸取教训的状态一直延续到真正有了教训，因此该空应填until引导时间状语从句。