Nǐ zěnme yòu chídào le?

你怎么又迟到了？

Why are you late again?

Notes:

你(nǐ): you

怎么(zěnme): why

又(yòu): again

迟到(chídào): be late

了(le): particle word

Example:

A：你怎么又迟到了？

     Nǐ zěnme yòu chídào le?

     Why are you late again?

B：对不起。

     Duì bù qǐ.

     I'm sorry.