我们是同学。

Wǒmen shì tóngxué.

We are classmates.

同一个问题，他已经问了三次。

Tóng yí gè wèntí, tā yǐjīng wèn le sān cì.

He has already asked the same question three times.

我和她有同样的兴趣，都喜欢看书和旅行。

Wǒ hé tā yǒu tóngyàng de xìngqù, dōu xǐhuān kànshū hé lǚxíng.

She and I have the same interests; we both like reading and traveling.