英语 fall over fall across的用法

I fell over the cliff.....
I fell across the table.

fall over
意外地从…上跌落, 掉下来
The car fell over a cliff and the driver was drowned.
汽车从悬崖上翻下来, 司机溺水而亡。
被…绊倒
He fell over a rock in his path.
他在小路上被一块石头绊倒了。
迫不及待做某事
Mother fell over herself to get the party ready.
母亲急切地为聚会做准备。
落在…之外
The ball fell over the line.
球落在线外。
fall across
横在…上
A big tree fell right across the road.
一棵大树倒下, 正好横在路上。
遇到
I happened to fall across her the next day in the park.
第二天我在公园里偶然遇到她。

1.@ fall over 朝某方向 占据某位置
Example：A shadow fell over the room.有个影子映在墙上.
2.@ fall over sb/sth 在行走时...脚碰到某人或某物而大趔趄或跌倒
Example ：he was fell over the bench.他碰到了凳子,打了一个趔趄.
3.@ fall over oneself 动作笨拙
4.@ fall over oneself to do sth 想法设法做某事或获取某物 .