£¨  £©39. The underlined word "stupid" in this passage means ____.

A. pretty                        B. happy

C. not clever                     D. not friendly

£¨  £©40. According to the last part, which of the followings is a good idea?

A. It's important for children to live with their parents.

B. It's helpful for people to see doctors every day.

C. It's useful for students to keep quiet in class.

D. It's necessary for young people to have group activities.