World Wildlife Fund (WWF)s goal is to save the worlds environment. The organization was

World Wildlife Fund (WWF)'s goal is to save the world's environment. The organization was set up 21 September 11，1961. In the beginning, WWF worked 22 the world's wildlife. Now, it works to save Earth 23 its environment.
WWF has many tasks. One is to stop air pollution. Pollution from industry(工业) and cars is _24_ to our environment. Each year, more and more trees are cut down 25 WWF tries to protect Earth's forests．Also people use more land, more and more animals are 26 their homes and many die. WWF can buy important areas to 27 the land from disappearing because of human development.
WWF has completed many projects. In China, WWF works to save pandas from extinction（灭绝）． 28 South America，it works to save the Amazon Rainforest. Volunteers and donations help WWF complete its work. WWF's work is 29 to our environment, and is also important for people to help them 30 time and money.
【小题1】A．inB．at C．onD．／【小题2】A．saveB．to save C．savingD．saved【小题3】A．and B．butC．orD．so【小题4】A．harmedB．harmlessC．harmD．harmful【小题5】A．because B．because ofC．soD．but【小题6】A．loseB．losingC．lostD．loses【小题7】A．giveB．provideC．prevent D．protect【小题8】A．AtB．On C．InD．To【小题9】A．hardB．importantC．easyD．useful【小题10】A．on B．aboutC．atD．withC

(答案→)C 解析：【小题1】在具体一天的前面用用介词on，故选答案为C【小题2】主要考查的是动词不定式短语表示目的状语，故选答案为B【小题3】本题中需要的引导的连接词为and，表示并列的意思。【小题4】do harfful to ，表示对于···他人，表示对于他人有害处。【小题5】前后两句子的关系为并列关系关系，故选and，答案为C【小题6】本题应该用现在进行时，其结构为主语+be+doing ，故选答案为B【小题7】prevent sb from doing表示阻止某人做某事。【小题8】在某个地名用介词in，表示在···地方，故选答案为C【小题9】be important to sb，表示对于某人是重要的，故选答案为B【小题10】help sb with sth，表示在某些方面帮助某人。

就是这个解释