slip multiple

例句：

1. 1. She slipped and fell onthe ice.
   她滑倒了。
2. 2. He tripped over a rock andhurt his leg.
   他绊倒了一块石头，摔伤了腿。
3. 3. The oldman slipped and almost fell off the chair.
   那位老人滑倒了，差点从椅子上摔下来。