问题
选择题
The field research will take Joan and Paul about five months; it will be a long time __________ we meet them again.
A．after
B．before
C．since
D．when
答案
B。
before引导时间状语从句。It will be a long time before…的意思是“要过很久才会……”，如：It will be a long time before we finish this dictionary. 我们需要很长的时间才能把这部词典编完。It was a long time before I got to sleep again. 过了好久我才又睡着。