If you have really been studying English for so long, it's about timeyou ____ able to write letters in English.
A) should be B) were C) must be D) are
这道题选B，为何A不对？it is about time虚拟语气有时不是也用should do吗
it is time sb did sth 结构中，should do偶尔用，但目前几乎淘汰了。最为容易见到的使用方法就是that从句用过去时。所以四选一是选最好答案，你应该选过去时were。并非should be是不对的，而是这种使用方法目前极少用。
