介词填空 There are two blackboards ___every classroom .One is ____us .The other is ___us

问题描述:

介词填空 There are two blackboards ___every classroom .One is ____us .The other is ___us

There are two blackboards in (在.里面) every classrom.One is in front of (在.前面),the other one is behind (在.后面) us.