fall fall back on求助于
Fall off On打开衰减
fall down on rainfall雨淋降落
fall bak on依靠
fall back on experiments求助于实验
fall back on upon求助于
Fall colors on campus校园的秋色
fall down on stage跌倒在舞台上
fall back on求助于;借助于;依赖;依靠
V（动词） to attack or snatch (an army, booty, etc) 袭击(军队); 抢夺(战利品) (See also fall upon)