It was not long until an ambulance arrived and rushed the injured man to a nearby hospital.
这现代大学英语2里的改错题。请问这个改错该怎么改啊，能具体说下原因吗？
句意：不一会一辆救护车就到了，急忙把伤员送到附近的医院。
【说明】应该把 until 改为 before 。因为 It was not [will not be] long before ... 是一个句型，意思是“不久 ......就”，如： It was not long before he came. 不一会他就来了。
