若矩形ABCD的对角线长为10，点E、F、G、H分别是AB、BC、CD、DA的中点，则四边形EFGH的周长是{#blank#}1{#/blank#} 

Thousands of trees must _______ every year.

完形填空

　　 The computer was one of the most important inventions in our life. The first computer was as large as a room.

Now some computers are as   1    as television sets. Some computers can even be smaller than a book. About 20 years ago, the computer was a strange machine in China. Not many people   2    it and said yes to it.

         Today much of that is   3 . In 1984, when Deng Xiaoping  4   two pupils working on the computers in Shanghai, he said that computer lessons     5 start from children. So there was the first computer book for middle school students. Now in Shanghai   6    all middle schools have classrooms for computer courses(课程). Some of the students now have their   7  computers at home. With the help of the Internet, they can send and    8   messages and e-mails. They can learn about the world more quickly.

         Now people are    9    using computers in banks, factories, airports and so on. The computer is coming into everyone’s life, so it is important to learn     10  to use a computer freely.

完形填空

　　 The computer was one of the most important inventions in our life. The first computer was as large as a room.

Now some computers are as   1    as television sets. Some computers can even be smaller than a book. About 20 years ago, the computer was a strange machine in China. Not many people   2    it and said yes to it.

         Today much of that is   3 . In 1984, when Deng Xiaoping  4   two pupils working on the computers in Shanghai, he said that computer lessons     5 start from children. So there was the first computer book for middle school students. Now in Shanghai   6    all middle schools have classrooms for computer courses(课程). Some of the students now have their   7  computers at home. With the help of the Internet, they can send and    8   messages and e-mails. They can learn about the world more quickly.

         Now people are    9    using computers in banks, factories, airports and so on. The computer is coming into everyone’s life, so it is important to learn     10  to use a computer freely.

在大课间活动中，体育老师对甲、乙两名同学每人进行10次立定跳远测试，他们的平均成绩相同，方差分别是=0.20，=0.16，则甲、乙两名同学成绩更稳定的是{#blank#}1{#/blank#} 

完成句子

①谢谢你借给我英语字典。

Thank you {#blank#}1{#/blank#} {#blank#}2{#/blank#} your English-dictionary to me.

②他决定打篮球而不是踢足球。

He decides to play basketball {#blank#}3{#/blank#} {#blank#}4{#/blank#} play football.

③ 他总是在晚饭后浏览晚报。

He always {#blank#}5{#/blank#} {#blank#}6{#/blank#} the evening newspaper after supper.

④ 森林将来会从地球上消失吗？

Will forest disappear from the earth {#blank#}7{#/blank#} {#blank#}8{#/blank#} {#blank#}9{#/blank#}?

⑤ 他每次将一粒花生扔进嘴里。

He threw the peanuts into his mouth one {#blank#}10{#/blank#} {#blank#}11{#/blank#} {#blank#}12{#/blank#}.

完成句子

①谢谢你借给我英语字典。

Thank you {#blank#}1{#/blank#} {#blank#}2{#/blank#} your English-dictionary to me.

②他决定打篮球而不是踢足球。

He decides to play basketball {#blank#}3{#/blank#} {#blank#}4{#/blank#} play football.

③ 他总是在晚饭后浏览晚报。

He always {#blank#}5{#/blank#} {#blank#}6{#/blank#} the evening newspaper after supper.

④ 森林将来会从地球上消失吗？

Will forest disappear from the earth {#blank#}7{#/blank#} {#blank#}8{#/blank#} {#blank#}9{#/blank#}?

⑤ 他每次将一粒花生扔进嘴里。

He threw the peanuts into his mouth one {#blank#}10{#/blank#} {#blank#}11{#/blank#} {#blank#}12{#/blank#}.

完形填空

　  It was not until books were produced that knowledge really    1   quickly around the world.

      For centuries, books were rare and very    2  . Each one was written    3     ! So it is understandable that one book took many months   4 . Today, a printer can produce    5    books in a day. Instead of being expensive, books these days are light, cheap and easy to get hold of. However many of these books are    6    ancient to be held and studied by many people. They need to be kept     7 away from danger. So here in the British Library, the latest technology has  8 download pages of these books onto a computer. This system has been developed   9     readers will be able to touch, read and study these beautiful ancient books. Have a look at the screen here. It is possible   10    the pages of the book, just as you would turn a normal book, by pressing a button. And on this part of the screen, helpful information about the book is displayed.

完形填空

　  It was not until books were produced that knowledge really    1   quickly around the world.

      For centuries, books were rare and very    2  . Each one was written    3     ! So it is understandable that one book took many months   4 . Today, a printer can produce    5    books in a day. Instead of being expensive, books these days are light, cheap and easy to get hold of. However many of these books are    6    ancient to be held and studied by many people. They need to be kept     7 away from danger. So here in the British Library, the latest technology has  8 download pages of these books onto a computer. This system has been developed   9     readers will be able to touch, read and study these beautiful ancient books. Have a look at the screen here. It is possible   10    the pages of the book, just as you would turn a normal book, by pressing a button. And on this part of the screen, helpful information about the book is displayed.

完形填空

　  It was not until books were produced that knowledge really    1   quickly around the world.

      For centuries, books were rare and very    2  . Each one was written    3     ! So it is understandable that one book took many months   4 . Today, a printer can produce    5    books in a day. Instead of being expensive, books these days are light, cheap and easy to get hold of. However many of these books are    6    ancient to be held and studied by many people. They need to be kept     7 away from danger. So here in the British Library, the latest technology has  8 download pages of these books onto a computer. This system has been developed   9     readers will be able to touch, read and study these beautiful ancient books. Have a look at the screen here. It is possible   10    the pages of the book, just as you would turn a normal book, by pressing a button. And on this part of the screen, helpful information about the book is displayed.

已知a、b为两个连续整数，且a＜$\sqrt{17}$＜b，则a+b={#blank#}1{#/blank#} 

计算：${\left(-1\right)}^2\times {\left(\frac{1}{2}\right)}^{-2}-{\left(\mathrm{\pi }-\sqrt{3}\right)}^0$={#blank#}1{#/blank#}