1. ___ in the air, fuels give off heat.

　　A. To burn B. Burned C. To be burned D. Being burned

　　【答案】B分词做状语。fuel是burn的宾语，因此使用被动式;前半句相当于省略了的状语从句，全句为When fuels are burned in the air, fuels give off heat.

　　2. ____ from space, our earth, with water covering 70% of its surface, appears a “blue planet”.

　　A. Seen B. Seeing C. To be seen D. Having seen

　　【答案】A 本题考察非谓语动词;see 的逻辑主语是句子的主语，即the earth, 是see (看)这个动作的对象，二者之间为动宾关系，所以应该用被动式。

　　3. ________ by the beauty of nature, the girl from London decided to spend another two days on the farm.

　　A. Attracting B. Attracted C. To be attracted D. Having attracted

　　【答案】B 被美景吸引，因此选被动

　　4. They sent us their statement, ___ to get our support.

　　A. hoped B. to hope C. hoping D. having hoped

　　【答案】C如果选A项,则它前面应有and,与主句构成并列关系. 排除A. to get our support本身即表示目的，没有必要再在前面加上不定式to hope表示目的,故排除B.而D项表示完成,从句没有完成的意思.故选C,现在分词短语作伴随状语. 句意是“他们给我们发了声明,希望获得我们的支持.”

　　5. When asked why he went there, he said he was sent there ______for a space flight.

　　A. training B. being trained C. to have trained D. to be trained

　　【答案】D。他被送到那里进行太空航行训练。