Some people are afraid of flying, which limits their options when traveling.
一些人十分害怕坐飞机,这也就限制了他们旅行时的选择了。
The Hubble telescope was launched into space by NASA on April 20,1990 at a cost of over a billion dollars.
哈勃望远镜于1990年4月20日由国家航空航天局发射升空,耗资10多亿美元。