怀疑

Get out of it!
别瞎说了
A: You can turn to David for help.
你可以找大卫帮忙。
B: Get out of it! He is the last one you can rely on.
别瞎说了！他是最不可信赖的人。

I don't have great belief in ads.
我不太相信广告的宣传。
A：The ad says one must do exercise with their equipment to keep healthy.
广告说要想健康就得用他们的器材来锻炼身体。
B: I don't have great belief in ads. What they really want is to get more money from you.
我不太相信广告的宣传，他们只想更多地赚你的钱。
ad= advertisement“广告”

Never tell me!= Tell me another!= That story isn't good enough for me.
我才不信呢！

I don't buy your story.
我不相信你的鬼话。
A: I have won the scholarship.
我获得了奖学金。
B：I don't buy your story.
我不相信你的鬼话。
scholarship n. 奖学金

I doubt.
我怀疑这件事。
A: He said he had seen the princess.
他说他见到公主了。
B：I doubt it.
我怀疑这件事。

So what?
那又怎么样呢？
A: He said he would think about our plan this time．
他说他这次会考虑我们的计划。
B: So what? He never likes others' ideas and he never has any ideas of his own.
那又怎么样呢？别人的点子他从来不喜欢，他自己又想不出点子。
“So what?“表示不屑一顾，不在乎或怀疑对方所提出的问题。

His decision is doubtful.
他的决定值得怀疑。
There's some doubt as to his decision.
对他做出的决定有一点怀疑。
doubtful a. 令人怀疑的

I find it hard to believe.
我觉得很难相信。
I think it's incredible.
我认为那难以置信。
A: I'm going to travel around the world.
我要去环游世界。
B: I find it hard to believe.
我觉得很难相信。

Don't expect me to believe you．
别指望我会相信你。
Do you expect me to believe that?
你以为我会相信吗？
expect v. 期望，（口）料想，认为

I'II believe it when I see it．
我要亲眼见到才能相信。
A：We have found your lost dog.
我们找到了你丢失的小狗。
B: I'll believe it when I see if.
我要亲眼见到才能相信。