她tā是shì第dì一yī名míng。

She is number one.

这zhè是shì我wǒ第dì一yī次cì来lái。

This is my first time here.

他tā是shì我wǒ们men班bān的de第dì一yī名míng。

He is the first in our class.

她tā得dé了liǎo第dì一yī名míng。

She came first place.

安ān全quán永yǒng远yuǎn是shì第dì一yī位wèi。

Safety always comes first.