开卷有益

kāi juàn yǒu yì

reading is always worthwhile

Character by character

开kāi
open

卷juàn
scroll

有yǒu
has

益yì
benefit

开卷有益，有空就多读点书吧。

Reading always pays off, so read more when you have time.

Tone: positive (praise).

卷 juàn = scroll, book (as in 试卷).

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