儿子每天给妈妈打电话。

Érzi měitiān gěi māma dǎ diànhuà.

The son calls his mom every day.

他们有一个儿子和一个女儿。

Tāmen yǒu yí gè érzi hé yí gè nǚ'ér.

They have one son and one daughter.

我儿子今年五岁了。

Wǒ érzi jīnnián wǔ suì le.

My son is five years old this year.