抛射剂
参考答案:
是喷射药物的动力,有时兼作溶剂,多为常压下沸点低于室温的液化气体。
In the United States, children start school when they are five years old. In some states they must stay in school until they are sixteen. Most students are seventeen or eighteen years old when they leave secondary(中等的) schools. There are two kinds of schools in the United States: public schools and private(私立的)schools . Most children go to public schools. Their parents do not have to pay for their education because the schools receive money from the government. If a child goes to a private school, his parents have to get enough money for his schooling. Some parents still prefer private schools, though they are much more expensive. Today about half of the high school students go to universities after they finish the secondary school. A student at state university does not have to pay very much if his parents live in that state. But many students work while they are studying at universities. In this way they develop good working habits and live by their own hands.
小题1: Children can go to school at the age of four in the U.S.
小题2:Most parents prefer to send their children to private schools in America.
小题3:About fifty percent of high school students can go on to universities after they leave the secondary school today.
小题4:Lots of American students go to universities by depending on their parents completely (完全地).
小题5:The passage is mainly about American education.
某集装箱船总长100m,最大宽度25m,前桅灯高度12m,舷灯位于前桅灯的前面,高度10m,左红右绿,离船舷2.2m,请问该船舷灯布置哪些不正确?()
A.舷灯位于前桅灯的前面
B.舷灯在船体以上的高度10m
C.左红右绿D.舷灯离船舷的距离超过2.2m