ump into:撞到（某人）,闯入/撞破（某件事情）
e.g.I accidentally bumped into a man and knocked him over.---我不小心撞倒了一个男人.
It's not her fault that she just bumped into this whole messy business.---闯进这件糟心事又不是她的错.
dump into:倒进（某件容器）
e.g.Factories should be condemned for dumping wastes into the nearby rivers.---工厂应当为把废弃品倒入附近的河流的行为而受到谴责.