问题 这里为什么用it

What language is it they are speaking？他们讲的是什么语？老师这句话可以直接这么说吗？what language are they speaking？另外这里为什么用进行时？谢谢！

话题 as it were

话题 as it is

话题 it is said

话题 be it time

话题 as it did

话题 have it good

话题 as it happened

话题 if it rains

话题 it was that

话题 get it wrong

话题 Is it really

话题 it-cleft

话题 all around it

话题 it was until