关于介词的
There was not a breath of wind and yellow leaves fell off trees _______themselves.(A)
A.of B.for C.by D.to
_______their efforts,the students can't get a mark high enough to please their parents.(D)
A.With B.Under C.In D.For
It was a small room 2.4 meters _________4.(D)
A.across B.to C.for D.by
--Is she older than you?
--Yes,she is older than I ________two years.(B)
A.to B.by C.for D.over
解释下每题的意思和选这个答案的原因.