单项选择题A.Average tuition costs increased by 9 percent.B.Average tuition costs increased by 15 percent.C.Average tuition costs increased by 90 percentD.Average tuition costs increased by 150 percent.
单项选择题A.Because many people don’t know how to behave in social situation.B.Because most people are shy by nature.C.Nobody will laugh at you for being shy.D.Shyness is difficult to overcome.