英语高手、数学高手请进!
一道英语智力题：
May,her sister,her daughter,and her son are playing volleyball.Her sister is directiy(刚好）across(交叉的、对面的）the net(球网）fron her son.Her daughter is diagonally(对角的)across the net from the best player's sibling(同胞兄弟姐妹）.The best player and the worst(最差的）player are on the same of the net.Who is the worst player?
答案：May'sister.
我不知道解题过程,希望高手帮个小忙,谢谢啦~~~