500　wear out和be worn out

1　wear out 意为“穿破，用坏”，结构为：

wear out+名词

wear+代词 +out

He wore out two pairs of shoes in one mouth. 他在1个月内穿坏了两双鞋。

He has worn them out . 他把它们穿破了。

He has worn out the bike. 他那辆自行车已经骑坏了。

2　be worn out 在形式上是wear out的被动语态，但表示的是状态，意为“穿破了”，用作表语，主语只能是物。

These shoes are worn out . 这些鞋子已经破了。

His shirt was worn out , so he bought a new one. 他的衬衫穿破了，所以他买了一件新的。

提示

be worn out还可表示“精疲力竭”，相当于be very tired, be tired out。

He was worn out after a whole day's work. 工作一整天后他十分疲劳。