短文改错 Your teacher of maths has taught you when to 1． find the centre of a circle

　Your teacher of maths has taught you when to 

1． ________

find the centre of a circle! It takes sometime． 

2． ________

Here is a simple method．

Put the corner of a sheet of paper in the 

3． ________

circumference (圆周) of the circle, then make 

4． ________

points A and B which the sides of the paper 

5． ________

across the circle． You may be sure that points

6． ________

A and B mark the end of a diameter (直径)． 

7． ________

To draw it, then repeat this process at a 

8． ________

different place to get other diameter．

9． ________

You will find the centre where two lines cross． 

10． _______

1． when 改为 how 

2． sometime 改为 some time

3． in改为 on 

4． √

5． which 改为 where 

6． across 改为 cross

7． end 改为 ends 

8． To draw 改为 Draw

9． other 改为 another 

10． two 前加 the