悬崖勒马

xuán yá lè mǎ

to pull back just before disaster

Character by character

悬xuán
hanging

崖yá
cliff

勒lè
rein in

马mǎ
horse

好在他及时悬崖勒马，没有越陷越深。

Luckily he pulled back in time before he got in deeper.

Tone: positive (praise).

勒 is lè here. Common in warnings: 希望你悬崖勒马.

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