He is a slippery customer, and should be carefully watched.

他可是个狡猾的主顾，得小心看着他。

《柯林斯英汉双解大词典》

Don't believe what he says—he's a slippery customer.

他说什么你可别信—他是个滑头。

《牛津词典》

Garfield is a slippery customer; he's twice escaped from police custody.

加菲尔德是个狡猾的家伙，两次逃脱警察的拘捕。

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So should the Swede be seen now as a slippery customer, or as a football coach who had achieved modest success with England, and who is entitled to his private life?

BBC: SPORT | Football | Internationals | How did Eriksson survive?