吉林市对600名中学生进行过一次采用问卷和访谈等方式的调查，当问及“业余时间最喜欢和谁在一起”时，80.7%的学生回答是同伴。调查显示，身为独生子女的中学生更重视同学间的友谊。

中学生物学科兴趣小组在学习了“青蛙的生殖和发育”后，开展“各种污染物对青蛙受精卵孵化率的影响”的探究活动。

他们采集了一定数量的青蛙受精卵，以化肥、洗涤剂作为污染物，在鱼缸中进行实验观察。

 ①他们作出的实验假设是：各种污染物会降低青蛙受精卵孵化率。

 ②将3个鱼缸中加入等量的清水，并编号1、2、3；在1、2号鱼缸中分别加入一定量的化肥、洗涤剂。

 ③把青蛙受精卵分成三等份(各100粒)，分别放人上述鱼缸中，在相同适宜的环境中孵化。

回答下列问题：

    It's Sunday morning. There are many people in the park, some boys are playing basketball. There are some girls under a big tree. They're singing and dancing. What are those women doing? They are drinking tea. Look at the woman in a blue coat. Who's she? She's my mother. She is talking to Edward. Edward is her student. He is a good student. He studies hard. He's good at all the subjects. And he's friendly to all his teachers and his friends.