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问题 选择题
如果分式
x+2y
x-y
中的x、y都扩大为原来的2倍，那么分式的值（　　）
A．扩大为原来的2倍B．缩小为原来的2倍
C．扩大为原来的3倍D．不变
答案

分别用2x和2y去代换原分式中的x和y得，

2x+2•2y
2x-2y
=
2(x+2y)
2(x-y)
=
x+2y
x-y
，

所以，分式的值不变．

故选D．

填空题

How did the Olympic Games start In ancient Greece athletic festivals were very important and had p ________ (1). Originally the Festival was held in honour of .Zeus, the supreme god in Greek Mythology. Eventually the Olympian athletic festival had lost its ________ (2) and became an international event. No one knows exactly ________ (3) the Olympic Games go, but some scholars recorded date from 776 B.C.According to some scholars, at first the only Olympic event was ________ (4), called a stadium and that was the only event until 724 B.C. After that, other ________ (5) were added and sixteen years later in ________ (6) the pentathlon was added and wrestling became part of the games. This pentathlon was a five-event match which ________ (7) running, wrestling, leaping, throwing the discus, and hurling the javelin.The games were held ________ (8) and after an uninterrupted history of 1170 years, the games ________ (9) in A.D. 394, the Christian era, because of their pagan origin.It was over ________ (10) before there was another such international athletics gathering. In 1896, the first of the modern ________ (11) opened in Athens, Greece.Nowadays, the Games are held in different countries ________ (12). The host country provides vast facilities such as stadiums and ________ (13).Many more sports are represented, including the very celebrated event: ________ (14).The Olympics start with the arrival in the stadium of a torch, ________ (15) on Mount Olympus by the sun’s rays. The torch is carried by ________ (16) to the stadium. The Olympic flame symbolizes the ________ (17) of the ancient Greek athletic ideals, and it burns throughout the Games until ________ (18). The well-known Olympic flag, however, is ________ (19): the five interlocking rings symbolize the uniting of all five continents ________ (20).
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