骑虎难下

qí hǔ nán xià

unable to back out

Character by character

骑qí
ride

虎hǔ
tiger

难nán
hard

下xià
get off

项目已经投了这么多钱，现在骑虎难下。

We’ve sunk so much money into the project there’s no backing out now.

Tone: neutral.

Once on the tiger’s back you cannot get off; 难 is nán.

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