前途渺茫前途茫茫qián tú miǎo máng

the future is a sealed book; the future looks grim (/bleak); with an airy (/a bleak/a gloomy) future;with nothing definite in view; with remote (/hazy/misty/uncertain)prospects
❍ 悲观主义者总觉得～，只有乐观主义者才对未来充满信心。Pessimists always feel that their future is a sealed book,whereas optimists are fully confident in their prospect.

前途渺茫qián tú miǎo mánɡ

渺茫：没有把握，看不见前途。比喻前途暗淡。feel that one’s prospects are black, with nothing definite in view, have an uncertain future