一落千丈

yī luò qiān zhàng

to plummet

Character by character

一yī
one

落luò
drop

千qiān
thousand

丈zhàng
zhang

那次丑闻以后，这位明星的人气一落千丈。

After that scandal, the star’s popularity went into free fall.

Tone: negative (criticism).

丈 is an old unit of about three metres; used of grades, prices and reputations.

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