自相矛盾

tā de huà zì xiāng máo dùn

她的话自相矛盾。

What she says is self-contradictory.

nǐ nán dào bù shì zì xiāng máo dùn ma

你难道不是自相矛盾吗？

Aren't you contradicting yourself?

wǒ men tǎo lùn le tā nà zì xiāng máo dùn de lùn diǎn

我们讨论了他那自相矛盾的论点。

We discussed the contradiction of his arguments.

zhè yàng jiě shì qǐ fēi zì xiāng máo dùn

这样解释岂非自相矛盾？

Wouldn't it be self-contradictory to put it that way?