初二英语补全对话,1.Most children are seventeen or eighteen years old

初二英语补全对话,
1.Most children are seventeen or eighteen years old when they f______high school.
2.High school students take only four or five s________each them.They usually go to the same classes every day,and thy have homework for e_______class.
3.So many college students w______after class to earn money for their studies.