级(jí) - level, grade; year (at school); step in Mandarin

我wǒ妹mèi妹mei今jīn年nián上shàng三sān年nián级jí。

My younger sister is in the third year of primary school this year.

他tā已yǐ经jīng通tōng过guò了leHSK四sì级jí考kǎo试shì。

He has already passed HSK level 4.

这zhè个ge班bān是shì初chū级jí班bān，那nà个ge是shì高gāo级jí班bān。

This is the beginners' class, and that one is the advanced class.

台tái风fēng来lái了le，风fēng力lì已yǐ经jīng到dào了le八bā级jí。

The typhoon has arrived and the wind has reached force 8.

这zhè个ge楼lóu梯tī有yǒu二èr十shí级jí。

This staircase has twenty steps.