You're too pessimistic.

你太悲观了。

I disagree with your pessimism.

我不赞成你的悲观态度。

I have lost hope for the result. （not hopeful about）

我对结果不抱希望。

I don't want to be infected with your pessimism.

我不想被你的悲观主义传染。

A: George, you're about to play, do you have cold feet?

乔治，你马上就要上场比赛了，很紧张吗？

B: To be honest, I'm not nervous because I'm not very hopeful about the game.

说实话，我不怎么紧张，因为我对这场比赛并不抱什么希望。

A: Why do you say so? I've never heard you say such pessimistic words.

为什么这么说？我从来没听过你说这么悲观的话。

B: I say for a reason. The player against me is much stronger than I, and I'm really not confident getting the better of him.

我这样说是有原因的。和我对决的那位选手比我强壮多了，我实在没信心打败他。

A: Come on, how can you grow the aspirations of others to outdo yourself. Didn't you beat someone stronger than you before?

拜托，你怎么能长他人志气灭自己威风呢？你以前不是打败过比你强悍的人吗？

B: It's different this time. I'm facing with the boxer called Tyson. So far, he hasn't lost all the cumulative competitions. Isn't it horrible?

这次可不一样，我要面对的是一位叫泰森的拳击手。到目前为止，他在所有的累积赛中还没有输过，是不是很可怕？

A: So what? You have your own strengths. As long as you give the flexible advantages into the play, I'm sure you can make it.

那又怎么样？你也有自己的强项，只要你在比赛中发挥自己灵活的优势，我相信你可以成功的。

B: My advantage can hardly stand a fight before him.

我的优势在它面前简直是不堪一击。

A: Your idea is too pessimistic. Clear it up quickly.

你这个想法太悲观了，赶快把它清理出去。