防微杜渐

fáng wēi dù jiàn

to nip a problem in the bud

Character by character

防fáng
guard

微wēi
tiny

杜dù
block

渐jiàn
creeping

孩子撒谎要及时纠正，防微杜渐。

Correct a child's lying early, before it becomes a habit.

Tone: positive (praise).

杜 = block. Common in discipline, safety and anti-corruption campaigns.

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