The boat sank in a violent storm at sea.

船在海上强烈的风暴中沈没。

He dreamt that he was at sea.

他梦见他在航海。

I am all at sea in the adolescent stage of my life.

刚刚成长起来的我陷入了迷茫之中。

She tried to understand the instructions, but she was completely at sea.

她费尽力气想看懂那些说明文字，却全然不知所云。