不行！bù xíng ！No！ 不对。bù duì .That's not right! 我不同意。wǒ bù tóngyì. I don't agree. 我不这样认为。wǒ bù zhèyàng rènwéi. I don't think so. 这样不太好吧。zhèyàng bù tài hǎo ba. It doesn't sound good.