我反对。

I don't agree. *比I can't agree.的语气还要强烈，给人一种直接反对的印象。

I know I'm correct. (我认为我是正确的。)

I don't agree. (我不这样认为。)

I don't agree with that.

I don't agree with you.

I agree. (同意。)

我不能同意。

I can't agree. *“我不能同意你的意见”，比较礼貌的说法。

All politicians are liars. (所有的政治家都是骗子。)

I can't agree. (我不能同意。)

I can't agree with that.

I can't agree with you.

我怀疑。

I doubt it.

Do you think it's true? (你觉得那是真的吗?)

I doubt it. (我怀疑。)

I don't think so.

It's not likely to happen. (才不会发生呢!)

我反对。

Objection!

We found out that he wasn't there. (我们发现他没有在那儿。)

Objection! (我反对。)

I object!

你不是这么说的。

That's not what you said.

You didn't say that.

我无法相信。

I can't buy that! *buy 除了“买”以外，还有“相信”、“承认”的意思。

I'm telling the truth. (我说的都是真的。)

I can't buy that! (我无法相信。)

That doesn't make sense. (那不合乎道理。)

That's ridiculous! (那太荒谬了。)

I refuse to believe that. (我不敢相信。)

馊主意。

Bad idea. *用于不同意对方的提议时。

Let's cheat. (我们糊弄一回吧。)

Bad idea. (馊主意。)

That's a bad idea.

That's not a good idea.

Not a good idea.

Good. (好哇。)

那可不好哦!

No good. *用于否定对方的意图、打算、计划时。是“那样不好”、“不行”的意思。这种表达方式让人觉得说话人有与对方不同的主意。

How is it? (怎么样?)

No good. (那可不好哦!)

That's no good.

Good. (那很好。)

算了吧!

Let's not. *否定、拒绝对方的提议、定义、暗示。

Let's go drinking. (我们去喝酒吧!)

Let's not. (算了吧!)

那怎么可能。

That's impossible. *很有把握时。

He's guilty. (他有罪。)

That's impossible. (那怎么可能。)

Impossible.

That can't be.

那完全是胡说八道。

That's absolute nonsense.

I saw you steal the money. (我看见你偷人家钱了。)

That's absolute nonsense. (那完全是胡说八道。)

Don't be so unreasonable. (别那么不讲道理。)

That's out of the question. (那根本不可能。)

That's quite impossible. (那根本不可能。)

行不通。

It won't work. *意为“好像怎么也不行”、“好像不顺利”、“好像不妥当”，是No good的较正式的表达方式。

I think it's a good idea. (我觉得那是一个好主意。)

It won't work. (恐怕行不通。)

It will work. (看起来不错。)

不总是这样。

Not always.

You always work late. (你总是工作到很晚啊。)

Not always. (不总是这样。)

不是那样。

Not really. *不能同意对方的意见或信息时，有礼貌地加以否定。

Do you want to go out for dinner? (你想不想去外面吃晚饭?)

Not really. (不太想去。)

Was it fun? (有意思吗?)

Not really. (不怎么有意思。)

It must be expensive. (这个一定很贵吧!)

Not really. (也不那么贵。)

Not especially.