英语中的 a grey area 意思是灰色地带或没有明确正误答案的、含糊不清的一个问题。

例句

When it comes to the law there are many grey areas.

The difference between flirting and harassment is a grey area.

请注意

另一个短语 shades of grey 有类似意思，通常在正误界定不清的时候使用。

Many children's stories say the world is full of black and white choices. In reality there are many shades of grey.