单项选择题
A.They reveal the seriousness of the problem. B.They indicate how fast the virus spreads. C.They tell us what kind of medicine to take. D.They show our body is fighting the virus.
A.She knows how to write best-selling novels. B.She can cam a lot of money by writing for adults. C.She is able to win enough support from publishers. D.She can make a living by doing what she likes.
A.Declining health. B.Lack of attention. C.Loss of motivation. D.Improper behavior.