prove difficult 和 prove to be difficult 有什么区别?

题目

prove difficult 和 prove to be difficult 有什么区别?
The operation proved to be difficult.
Rescue operations are proving difficult.

答案

二楼的观点是错的
我很负责任地说,这两种表达意思相同,而且都是正确的!
to be 省略时,prove相当于系动词(系动词你应该明白吧,就像look,sound后面可以直接加形容词,举个例子:You look great today!你今天看起来很棒啊!）