乐此不疲

lè cǐ bù pí

never to tire of something

Character by character

乐lè
enjoy

此cǐ
this

不bù
not

疲pí
tire

他每天拍照修图，乐此不疲。

He takes and edits photos every day and never tires of it.

Tone: neutral.

Of a hobby someone happily repeats; 乐 is lè.

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