2023年12月28日发(作者：初三数学试卷题型分析)

圆中心的这一点叫做圆心，用字母O表示。圆心决定圆的位置。

通过圆心并且两端都在圆上的线段叫做直径，用字母d 表示。两端都在圆上的线段，直径最长。

连接圆心和圆上任意一点的线段叫做半径，用字母r表示。半径决定圆的大小。

在同一个圆里，直径是半径的２倍，半径是直径的。在同一个圆中，所有的半径都相等

d=2r r=d r:d=1:2

用圆规画圆的步骤：一、定长；二、定点；三、旋转。

封闭图形一周的长度叫做这个图形的周长。

一个圆的周长总是它的直径的3倍多一些（π倍），我们把它叫做圆周率，用字母“π”表示，它是一个无限不循环小数。π＞3.14

圆的周长公式：C = πd C = 2πr

d= C÷π r= C÷π÷2

把圆切成若干大小相等的扇形，拼成长方形，这个长方形的长是圆的周长的一半，长方形的宽是圆的半径。所以圆的面积公式是：

S =πr2

圆环的面积公式：S =π（R2-r2）

有直径的半圆周长公式：C=πr+2r C=πr+d

半圆的面积公式：S=πr2÷2

π≈3.14 2π=6.28 3π=9.42 4π=12.56 5π=15.7

6π=18.84 7π=21.98 8π=25.12 9π=28.26 10π

1212

=31.4

16π=50.24 32π=100.48 64π=200.96 25π=78.5

18π=56.52 36π=113.04

Unit 1 Can you play the guitar？

一、单项选择：

( ) 1. —Can Lisa play the piano? —Sorry, she .

A. don’t B. do C. can’t

( ) 2. Peter can play the violin he can’t play it very well.

A. or B. and C. but

( ) 3. Jill can very well, so he wants to join the club.

A. swim; swimming B. swimming; swim C. swim; swim

( ) 4. My sister is good old people.

A. to B. at C. with

( ) 5. —Can your sister ________?—Yes. Here are some of her pictures.

A. draw B. swim C. dance

( ) 6. —Do you often play ________ soccer with your friends?

—No, I don’t like sports, I often play ________ piano on the weekend.

A. a; the B. the; / C. /; the

( ) 7. —I want to join your art club.—Can you draw well? —________. But I want to

learn it.

A. Yes, I can B. No, I can’t C. Yes, very well

( ) 8. —What can Li Xin do?—He can ________ Chinese Kungfu.

A. play B. do C. make

( ) 9. —You play the drums very well.—________.

A. Not good B. You’re welcome C. Thank you

( ) 10. My brother is good at ________ stories.

A. speaking B. saying C. telling

二、完形填空：

A: Hi, Peter. Let’s join a 1 . What club do you want to join?

B: Oh, I 2 know, Alice.

A: Well, 3 can you do? Can you play 4 ? Do you want to join the chess club?

B: No. I can’t play chess.

A: Do you like 5 ?

B: Yes, I 6 . And I can sing very 7 .

A: Great! Can you play the piano 8 the drums?

B: No, I 9 . But I can play the guitar.

A: You can play the guitar. I can play the drums. Let’s join the 10 club.

( ) 1. A. club B. class C. school

( ) 2. A. don’t B. can’t C. am not

( ) 3. A. how B. what C. when

( ) 4. A. soccer B. games C. chess

( ) 5. A. drawing B. swimming C. music

( ) 6. A. can B. do C. want

( ) 7. A. nice B. good C. well

( ) 8. A. or B. and C. but

( ) 9. A. can B. can’t C. may

( )10. A. music

三、阅读理解：

B. soccer C. art

A

Dear Mr. Wu,

I am Jack. I want to be in a club in our school. I can’t sing or dance or act in movies (电影),

but I can do many other things. I can play three instruments, the guitar, the violin and the piano. I

think I can be in the music club. Maybe (也许) I can be a famous (著名的) musician. I like

reading story books and I can write stories. Maybe I can be a famous writer. I like sports too, but I

don’t think I can be a famous and successful sportsman (运动员). Can I join you?

Yours,


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