slipped off的用法和樣例：
例句
- I thought I was safe on the branch, until my foot slipped off and I fell to the ground.
我一直以為自己在樹枝上很安全，沒想到腳步一滑，掉到了地上。 - His foot slipped off and fell to round.
他的腳踩滑了，摔到了地上。 - The book slipped off my knees.
書從我的膝蓋滑落下去。 - I saw him suddenly change colour, but before I could reach him he had slipped off his chair on to the floor in a faint.
我看到他突然臉色變白，急忙得去扶他，他已一陣昏暈，從椅上跌倒在地板上。
