helen hurts her leg while playing on the playgroud。a was playing b playing 为什么用playing

Question

如题所述

Answer 1

while （she is）playing.括号里的省略了，sb. is跟在when 和while后面是可以一起省略掉的

Answer 2

张道真英语语法，第239页：
在某一动作进行时，另一动作发生（这时分词短语前多加while或when）:
Be careful when crossing the road.过马路要当心。（=When you cross...）
He got engaged to her when travelling in Europe.在欧洲旅行时他和她订了婚。
She tremble a little while doing so.她这样做时稍稍颤抖了一下。
While trying to open the door,I cut my hand.在设法开门时我把手刺破了。

Answer 3

while当从属连词，引导时间状语从句，其谓语动词应使用延续性动词，海伦在操场玩时伤了她的腿，while：而
后面动作与之前同时发生

Answer 4

Helen hurts her leg while (she was ) playing on the playground.
while从句相当于省略了主谓。本回答被提问者采纳