Huángjīn bù dǎ, bù chéngqì.

黃金不打, 不成器。

Lit Gold without being hammered won't become [useful] utensils.

Fig Without education or training one will not (grow up to) be a useful person.

Note [Note: chéngqì, (lit) “become an instrument,” means to grow up to be a useful person; bùchéngqì is also an idiom meaning “good-for-nothing; worthless.”]

Topics bùchéngqì chéngqì EDUCATION TRAINING