feel blue的用法和樣例：
例句
- But the deeper you understand the sophisticate mankind, the more desperate you feel.
但你愈是了解復雜的人類(lèi)，你愈是感到沮喪絕望。 - Nationalism is built out of frustration that people feel when they cannot get their way through the ballot box.
如果不能通過(guò)選票箱自主行事，人民就會(huì )感到沮喪，而民族主義情緒的根源就是沮喪心理。
