流星体在快速穿过大气层时, 因磨擦而迅速加热.Moving swiftly through the atmosphere, meteoroids are heated rapidly by friction.如果流星体聚集在一起, 则每年看到的流星数都不一样.If the meteoroids are bunched together, the number of meteors seen varies from year to yea...
Television has irreversibly changed our perception of the Royal Family.电视不可逆转地改变了我们对皇室的印象。Human perception is highly imperfect and by definition subjective.人的感知具有高度缺陷，而且天性主观。our perception of reality我们对现实的认识...