Who are you w___ at when you got on the train?

题目

Who are you w___ at when you got on the train?
根据句意和所给首字母填单词啊,还有I must be o_____ for it's getting late.
Now many children can play a musical i_____.
顺便说出所填单词的意思啊,第一句后面有got ,不可能是现在进行时啊!!!

答案

waving招手
off离开
instrument乐器