pipe-dream 白日梦，不切实际的空想，幻想，空想

【例句】
You could waste your whole life on a pipe dream.
白日梦会荒废你一生。

For once in their life, a place where they won't have to worry about a thing, what do you think? Pipe dream, huh?
让他们有一个可以无忧无虑的地方，你觉得我的想法是不是白日梦？