1. fall apart [破裂；破碎；崩溃]
【构成】fall[落下；跌倒] ； apart[分开；破碎]
【例句】The old chair fell apart when I sat on it. [我一坐上去，那把旧椅子就散架了。]

2. fall behind [落后；拖欠]
【构成】fall[落下；跌倒] ； behind[在…后面]
【例句】If you don’t study hard, you’ll fall behind. [如果你不努力学习，你就会落后。]

3. fall down [跌倒；失败]
【构成】fall[落下；跌倒] ； down[向下]
【例句】She fell down and hurt her knee. [她跌倒了，伤了膝盖。]

4. fall for [爱上；受骗]
【构成】fall[落下；跌倒] ； for[为了；对于]
【例句】He fell for her at first sight. [他对她一见钟情。]
Don’t fall for his tricks. [别上他的当。]

5. fall in love [坠入爱河；相爱]
【构成】fall[落下；跌倒] ； in[在…里] ； love[爱]
【例句】They fell in love with each other last year. [他们去年相爱了。]

6. fall off [减少；跌落]
【构成】fall[落下；跌倒] ； off[离开；脱落]
【例句】Sales have fallen off recently. [近来销售额下降了。]
The leaves are falling off the trees. [树叶正从树上掉落。]

7. fall on [落到；袭击]
【构成】fall[落下；跌倒] ； on[在…上面]
【例句】The responsibility fell on him. [责任落在了他身上。]
The enemy fell on the village at night. [敌人在夜间袭击了这个村庄。]

8. fall out [争吵；脱落]
【构成】fall[落下；跌倒] ； out[出去；向外]
【例句】They often fall out over small matters. [他们经常为小事争吵。]
His hair is falling out. [他的头发在脱落。]

9. fall asleep [入睡；睡着]
【构成】fall[落下；跌倒] ； asleep[睡着的]
【例句】I fell asleep quickly last night. [昨晚我很快就睡着了。]

10. fall ill [生病]
【构成】fall[落下；跌倒] ； ill[生病的]
【例句】He suddenly fell ill yesterday. [他昨天突然生病了。]

11. fall into [落入；陷入]
【构成】fall[落下；跌倒] ； into[进入]
【例句】The boy fell into the river. [那个男孩掉进了河里。]
She fell into a deep depression. [她陷入了深深的沮丧之中。]

12. fall over [摔倒；跌倒]
【构成】fall[落下；跌倒] ； over[倒下；翻转]
【例句】He fell over and broke his leg. [他摔倒了，摔断了腿。]

13. take a fall [遭受挫折；失败]
【构成】take[拿；取] ； a[一个] ； fall[跌倒；失败]
【例句】He took a fall in his business. [他在生意上遭受了挫折。]

14. free fall [自由落体]
【构成】free[自由的] ； fall[落下；跌倒]
【例句】The object is in free fall. [这个物体在做自由落体运动。]

15. heavy fall [大量下降；大雨；大雪]
【构成】heavy[重的；大量的] ； fall[落下；跌倒]
【例句】There was a heavy fall of snow last night. [昨晚下了一场大雪。]

16. sudden fall [突然下降；突然跌落]
【构成】sudden[突然的] ； fall[落下；跌倒]
【例句】The stock price had a sudden fall. [股票价格突然下跌。]

17. autumn fall [秋天的落叶]
【构成】autumn[秋天] ； fall[落下；跌倒]
【例句】The autumn fall is very beautiful. [秋天的落叶很美。]

18. waterfall [瀑布]
【构成】water[水] ； fall[落下；跌倒]
【例句】We saw a magnificent waterfall on our trip. [我们在旅行中看到了一个壮观的瀑布。]

19. price fall [价格下跌]
【构成】price[价格] ； fall[落下；跌倒]
【例句】The price fall has affected our profits. [价格下跌影响了我们的利润。]

20. nightfall [黄昏；傍晚]
【构成】night[夜晚] ； fall[落下；降临]
【例句】We should arrive before nightfall. [我们应该在黄昏前到达。]