Question

______ Tom, we wouldn’t have been late for the last bus.

1. A.
   If we didn’t wait for
2. B.
   If we haven’t waited for
3. C.
   we hadn’t waited for
4. D.
   Had we not waited for

Answer 1

D
考查if非真实条件句的虚拟语气，从主句用wouldn’t have been，可知是if we had not waited…,这也可以变成had we not waited，选D，句意是：如果我们没有等汤姆，我们就不会赶不上最后一班车。选D。