至迟

zhè tiáo tiě lù zhì chí liù yuè tōng chē

这条铁路至迟六月通车。

This railway will be opened to traffic in June at the latest.

tā zhì chí míng tiān huí lái

他至迟明天回来。

He will be back no later than tomorrow.

nǐ zhì chí bù yào chāo guò liù diǎn dào dá nà lǐ

你至迟不要超过六点到达那里。

You should be there by six at the very latest.

zhè xiàng gōng chéng zhì chí sān yuè wán gōng

这项工程至迟三月完工。

The project will be completed by March at the latest.