3
for a long time --------很久以来,直到现今.----------用现在完成时
如果是until now,就应该是until now they haven't been able - - --
-------- not - -- until
not 要搭配 until
youyouniao84 09:07:23
这就不知道了
palmaking 09:07:31
for a long time 搭配unable
youyouniao84 09:07:47
答案错了?
palmaking 09:07:52
unable不是否定词
youyouniao84 09:08:07
哦
palmaking 09:08:26
至少,我是这样感觉的
youyouniao84 09:09:02