War(warm?)air is frequently lighter as the molecules bump around, excited by the heat.
暖空气经常更轻一些，因为分子受到热量的激励而四处碰撞。
The birds have little "sub-dural space" between their brains and their skulls, so the brain does not have room to bump around as it does in humans.
啄木鸟在它们的大脑和头骨之间几乎没有“次硬脑膜空间”，所以其大脑不像人类的一样在四周有凹凸不平。
Walk around any downtown district in a big city in China and you will likely bump into at least several foreigners, many to find a bargain in a department store or at a street stall.
漫步在中国任何一个大城市的市中心，你都可能碰到几个外国人，他们中的许多人想在百货商店或者地摊上猎取廉价商品。
Actually, the automobile insurance is more important than the homeowners' insurance, even though homes are so much more valuable, because--I think that's because cars move and they drive around and they bump into each other.
实际上,尽管住宅要比汽车值钱的多,但是,汽车保险要远比,住宅保险重要,我觉得这是因为汽车是可以移动的,车主们开着车到处跑,容易相互碰撞
金融市场课程节选 : 耶鲁公开课
All things equal, the most important determinant of an option's price is the implied volatility of the underlying asset over the life of the option how much it is likely to bump around.
Bump has been around since 2008.
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