A.从方框中选择正确的词,并用其适当的形式填空：
（change , use , few , realize , die）
1.Humans have come【to realize 逐渐意识到】that animals areimportant to us
2.So far , humans 【has changed 改变了】our planet in many ways .
3.Many kinds of animals and plants are 【dying绝种】out these years .
4.The government has done something【useful 有用的】to protect the environment
5.Because of the pollution , animals become fewer and 【fewer越来越少】