多年(duō nián) - many years in Mandarin

我wǒ们men认rèn识shi多duō年nián了le。

We have known each other for many years.

他tā在zài国guó外wài住zhù了le多duō年nián。

He lived abroad for many years.

多duō年nián的de努nǔ力lì终zhōng于yú有yǒu了le回huí报bào。

Many years of effort finally paid off.

这zhè是shì多duō年nián的de老lǎo朋péng友yǒu。

This is a friend of many years.

多duō年nián以yǐ后hòu，他tā回huí到dào了le家jiā乡xiāng。

Many years later, he returned to his hometown.