坚持不懈

jiān chí bù xiè

to keep at it without letting up

Character by character

坚jiān
firm

持chí
hold

不bù
not

懈xiè
slacken

他坚持不懈地练了十年书法。

He practised calligraphy tirelessly for ten years.

Tone: positive (praise).

Usually 坚持不懈地 + verb or 要坚持不懈; a staple of speeches and school essays.

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