下列变化中，属于物理变化的是（ ）
A．汽油挥发
B．食物变质
C．葡萄糖在人体内氧化
D．用富含淀粉的甘薯酿酒
A、汽油挥发是由液体变成蒸汽，没有生成其他物质是物理变化，故A正确；
B、食物变质不能再吃，说明有新的物质生成，属于化学变化，故B错；
C、葡萄糖在人体内氧化生成二氧化碳和水，属于化学变化，故C错；
D、用富含淀粉的甘薯酿酒说明有乙醇生成，属于化学变化，故D错．
故选A．
A man has returned three library books to a Melbourne library—21 years overdue（误期）.The books were returned to Sam Merrifield Library with a (n)__ 21___note and a $50 bill. ___ 22___Margaret Young was pleased that the books had been returned. They were in excellent___23__ , except for the one that the borrower admitted had been damaged by a___24___. “They’re all spy books. We were just surprised and___25 ___that he has returned the books, ___26 ___after so many years,” Mrs. Young said. The books were__ 27__on June 18, 1985 and would have to be paid almost $5,800 in overdue __28__. But, because of the sweet letter and $50 note, Mrs. Young said all was__29__. She said, “We thank him for returning the books and hope his conscience（良心）is __ 30 _. I’d like to think he can come back into the library one day to borrow more material__31__he returns it.” To whom it may concern, About 20 years ago I__32 __to return the three books to your library. In fact I__33__them.During that time, one of the books was damaged by my dog. I have enclosed all three books and a sum of money that will go some way toward __34__the damaged book. My __35__were unforgivable; a thief is a thief. Please __ 36__my apology for stealing the books and for not having the courage to return them__37__. I want you to know that for the last few years this theft has__38__my conscience and I am sorry I was so selfish to steal them in the first__39__. I hope this goes some small way to__40 __my actions.
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