我会换两个近义词。     

1．小马听了老牛的话。立刻跑到河边。     (      )  (      )

2．小马听了松鼠的话，马上收住脚步。     (      )  (      ) 

3．你的羽毛真漂亮。(      )  (      ) 

4．花园里的花开得非常鲜艳。     (      )  (      )

Did you know _____ at the bus stop? Maybe their teacher. [ ]

A. who are they waiting for

B. whom they are waiting for

C. whom they were waiting fot