There's something odd about the way that fellow is behaving . I am sure he's up to no good.

那个人形迹可疑,肯定要做坏事.

《简明英汉词典》

He's up to no good , ie doing sth bad.

他现在没干好事.

辞典例句

I guess the fellow is up to no good.

我猜这个家伙要图谋不轨.

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They come out after dark, up to no good.

他们天黑才露面, 不做什么好事情.

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You must be up to no good.

你一定不怀好意.

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I knew he was up to no good.

我知道他图谋不轨.

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Avoid any man who deals in micrograms, for he's up to no good.

别理睬那种龌龊的人, 这种人没安好心.

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Where's that naughty child now? I'm sure he'll be up to no good wherever he is.

那调皮孩子哪儿去了? 我看,他到哪儿也做不出好事来.

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Oh, up to no good are we? Let's see what you can do then.

哦, 在偶们面前看样子非常糟糕? 偶们瞧瞧你到底有啥本事?

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Look at him going around so furtively – surely he's up to no good.

瞧他贼头贼脑的样子就不像好人.

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