How long do you think it will be __ China sends a manned spaceship to the moon?ow long do you think it will be __ China sends a manned spaceship to the moon?A.after B.until C.that D.before
问题描述：
How long do you think it will be __ China sends a manned spaceship to the moon?
ow long do you think it will be __ China sends a manned spaceship to the moon?
A.after B.until C.that D.before
答
y选D
How long do you think it will be do you think是插入语 How long it will be
有多久 所以 后面应该是 在中国登月之前 所以 选before
答
D before
要过多长时间中国才能发射载人宇宙飞船登月？
答
D before
中国在发射载人飞船之前还要经历多久
答
D 在中国发射一个人造飞船到太空前要经历多少时间
时间状语从句，主将从现
答
D,记住before在疑问句中常与将来时连用,表示 过多久才.