题目

Long ago and faraway, there lived an old man and woman. One day, while the woman 1 clothes in the river, she saw a great big orange on the water moving slowly towards her. Excitedly, she caught the orange and decided 2 it home to eat. When the woman began to open the orange, suddenly, jumped out a little lovely boy! The man and woman didn’t know 3 . But they felt very happy and named the boy Bobonaro, or Orange Boy. As time went by, the boy became very strong and brave. Life was wonderful until some robbers（盗贼） moved onto a nearby island. The robbers were always stealing4 things f从4名男生和2名女生中任选3人参加演讲比赛,则所选3人中恰有1名女生的概率是         .