单项选择题A.It can make the speech better understood.B.It may help win the contest.C.It can make the audience vigorous.D.It can make the speaker confident.
单项选择题A.To caution young people not to send texts while driving.B.To teach young people how to drive their cars safely.C.To persuade parents to forbid young people to drive.D.To popularize knowledge and awareness about security.