Subject + 没用 + 了 / 对 + Person + 没用
没用 (méiyòng) means "useless" or "of no use," describing something that has no practical value or function. It is a colloquial and direct way to express futility. For example, 对你来说已经没用了 means "it's already useless to you."
光着急没用,你得想个办法才行。
guāng zhāojí méi yòng, nǐ děi xiǎng ge bànfǎ cái xíng.
Just worrying is useless; you need to think of a solution.
这把坏了的伞已经没用了,扔了吧。
zhè bǎ huài le de sǎn yǐjīng méi yòng le, rēng le ba.
This broken umbrella is useless now; just throw it away.
说再多好话也没用,他不会改主意的。
shuō zài duō hǎo huà yě méi yòng, tā bù huì gǎi zhǔyì de.
No matter how many nice things you say, it's useless; he won't change his mind.