托福作文
独立写作：是否同意：现代孩子很难教育，因为有电脑，社交网络，游戏，光玩了，不学习
综合：
1、海牛 灭绝是因为S族人大量捕杀造成的，听力说不可能，因为海牛体型庞大，就算用来吃也不用杀那么多
2、海牛灭绝第二原因是因为海藻数量减少导致海牛没食物而灭绝，听力中说海藻一直好好的，海牛不会缺吃的
3、 海牛灭绝最主要的原因是因为欧洲人到岛屿用武器**大量海牛，听力：在欧洲人来之前100年，海牛就已经很少了
综合写作
reasons for the extinction of sea cows.
reading, three theories
1. native S(地名)people kill them for food.
2. ecosystem distubances reduce the food resources of sea cows
3. European traded sea cow's fur, so they killed a large number of sea cows
listening disagree
1. sea cows are massive creature, they can provide enough food// the population of S people are small at that time
2. except extinctions of sea cows, no other species, like the whales extincted
3. the population of sea cows had already decreased before European arrived this eara. so there must something else to explain the extinction.