Unlike her ______ sister, Judith is a shy, unsociable person who dislikes to go to parties or to make new friends.
 
【正确答案】 D
【答案解析】 分析句子可知空格处应填与shy(害羞的)和unsociable(不爱交际的)意思相反的词,因此选gregarious(爱交际的,合群的)。