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The Great Wall of China Have you ever been to the Great Wall？The Great Wall of China is the longest wall in the world.It runs across north China like a huge dragon（巨龍）.It is about 6，000 kilometers long，7 meters high and 5 meters wide.In most places it is wide enough for five horses or ten men to walk side by side along the top.
   The Great Wall was built more than twenty centuries（世紀(jì)）ago.It was difficult to build such a great wall without any modern machines（現(xiàn)代化機(jī)器）.All the work had to be done by hand.It is very famous in the world.Many foreigners come to visit it every year.
（1）The Great Wall is the

B

B

wall in the world.
A．largest
B．longest
C．smallest
（2）The Great Wall is

B

B

kilometers long.
A．a(chǎn)bout 3，000
B．a(chǎn)bout 6，000
C．a(chǎn)bout 5，000
（3）The Great Wall is about

A

A

meters high.
A．seven
B．five
C．six
（4）When was the Great Wall built？

A

A

A．More than 20 centuries ago.
B．20 years ago.
C．We don't know.
（5）Did people use modern machines to build the Great Wall？

C

C

A．We don't know.
B．Yes.
C．No.