第二节简答题(共3小题；每小题2分，满分6分)
阅读下面短文，根据第73至第75小题的具体要求，简要回答问题。
Parents often believe that they have a good relationship with their teenagers. But last summer, Joanna and Henry noticed a change in their older son: suddenly he seemed to be talking far more to his friends than to his parents. “The door to his room is always shut,” Joanna noted.
