Thousands of meteorites penetrate Earth's atmosphere and fall harmlessly to the ground each year.每年,几千块陨石穿过地球大气,掉到地面上,并不会造成什么伤害.One theory about the existence of extraterrestrial life rests on the presence of carbon...
The mother kept a watch over the sick child all night.母亲整夜照顾生病的孩子.They kept a careful watch over the vineyard throughout the growing season.在整个生长季节,他们都认真地守着葡萄园.The guards were originally hired to watch over the houses as...