2014年5月12日，广东省珠海边防支队破获一宗涉嫌走私野生保护动物案件，当场查获穿山甲冻体956只，总重约4吨。保护野生动物、维护生态平衡，我们青少年能做的有（    ）

根据下列句子及所给单词的首字母，在答题卷上按题号写出各单词的完全形式（每空限填一词）。
⑴My grandfather likes to water the f____  in the garden on weekends.
⑵The boy is too young. So don't leave him a____  at home.
⑶If I don't help my mom do some h____  on weekends, my mother will be very angry with me.
⑷Last night I didn't go to bed u____  the TV program was over.
⑸Last Sunday I w____  a letter to my father.
⑹I need to look smart for my job i____ .
⑺He f____  his test last week. He should study hard.
⑻He m____  his teacher in the street yesterday.
⑼When the little girl saw the big tiger, she felt very s____ .
⑽Last week, I p____  500 yuan for my new bike.

已知椭圆C：$\frac{x^2}{a^2}$+$\frac{y^2}{b^2}$=1（a＞b＞0）的离心率为$\frac{\sqrt{6}}{3}$，焦距为2$\sqrt{2}$，过点D（1，0）且不过点E（2，1）的直线l与椭圆C交于A，B两点，直线AE与直线x=3交于点M．

（1）求椭圆C的标准方程；

（2）若AB垂直于x轴，求直线MB的斜率。