A policeman be all eyes all ears.

一个警察必须眼观六路,耳听八方.

A detective must be all eyes and all ears.

一个侦探必须眼观六路,耳听八方.

Now children, I want you to be all ears in class.

孩子们，我要求你们在课堂上专心听讲。

I will be all ears for people who have requests and feedback about absolutely anything.

我将所有的耳朵的人的要求和反馈意见，绝对什么。

To be all ears is an informal idiom, meaning ready to listen, or giving their full attention.

To be all ears是一个非正式的习语，意思是准备好倾听，或者全神贯注。