多duō多duō益yì善shàn

Literal: the more, the more beneficial
Figurative: The more the better; you can never have too much of a good thing.

Where does 多多益善 come from?

The first Han emperor, Liu Bang, was once chatting with his great general Han Xin about how many troops his officers could command. When he asked how many men he himself could lead, Han Xin said no more than a hundred thousand. “And you?” the emperor asked. Han Xin replied that for him, the more troops the better (多多益善). Liu Bang laughed and asked why, if he was so capable, he was serving under him; Han Xin tactfully answered that the emperor was no good at commanding troops, but excellent at commanding generals.

Source (出处): 《史记·淮阴侯列传》

How is 多多益善 used? Two examples

学xué外wài语yǔ的de时shí候hòu，多duō听tīng多duō说shuō，词cí汇huì当dāng然rán是shì多duō多duō益yì善shàn。
When learning a language, listen and speak a lot; as for vocabulary, the more the better.
这zhè次cì活huó动dòng的de志zhì愿yuàn者zhě多duō多duō益yì善shàn，你nǐ能néng来lái帮bāng忙máng吗ma？
For this event, the more volunteers the better. Can you come and help out?

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