at sea

1on the open sea在海上

The ship spent 40 days at sea 这条船在海上航行了40天。

2lost in mind not understandingpuzzlednot knowing what to do茫然;迷惑;不知所措

You are still all at sea He is an outandout scoundrel.你还蒙在鼓里,他是一个十足的流氓。

The job was new to him and for a few days he was all at sea 他刚开始干这活,有好几天他都糊里糊涂的。

He is quite at sea as to what measures should be taken to settle the problem.他全然不知该采取什么措施来解决这个问题。

She was quite at sea in regard to that matter.说到那件事,她实在茫然。