根据短文内容及首字母提示，补全空格内单词，使短文完整、通顺。

    In the United States, children start school when they are five years old. In some states they must

stay in school (1)u            they are sixteen. Most students are seventeen or eighteen years old when

they (2)l            high school. There are (3)t            kinds of school in the United States: public school

and private school. (4)M            children go to public schools. Their parents do not have to (5)p            

for their education because the schools receive money from the government. If a child goes to a private

school, his parents (6)h            to pay enough money for his schooling. Some parents still choose private

schools, though they are much more (7)e           . 

   Today about half of the high school students go to universities (8)a            they finish the high school.

A student at a state university does not have to pay too (9)m            if his parents live in this state. 

    But many students work while they are studying at universities. In this way they can have good working

habits and live by their own (10)h           .