题目内容
The Internet can be a great way to connect with people.The latest web craze is social networking on websites such as MySpace.More than 65 million young people use online social networking sites.
That cyberspace(网络空间)trend is causing problems in school,however.In a recent survey,nearly 36 percent of school administrators said that social networking sites troubled learning in their districts.Should school districts ban sites like MySpace?
Teachers are worried that some students use social networking to post personal information and to cyber bully(恐吓)other students.One of the biggest dangers comes from people who find out kid’s personal information.
Many districts have blocked students from accessing or using social networking sites from school computers,and some have suspended(暂缓)students for posting harmful material on those sites from their home computers.Nearly two-thirds of US kids have computers in their homes,according to the US Census Bureau.
It is important to keep in mind that just blocking access to social web sites at school is not the end of the story,” warns NSBA executive director Anne Bryant,“Most of the misuse of these sites takes place at home but still affects the classroom.”
Some educators aren’t as quick to pull the plug on social networking.They say the main problem with sites like MySpace is that students don’t understand the dangers involved in using them.“Many students are posting personal information about themselves without regard to who has access to that information,”Jim Hirsch said,“Schools should focus on educating their students and their parents on how to be safe online.”
Experts argue that too many schools are forbidding students to use social networking web sites without thinking about their educational benefits.“Social networking web sites can help connect students in the United States to their peers in other countries, providing invaluable lessons in foreign cultures,”explains Hirsch.
1.Where do students usually misuse social networking sites?
A. At the teacher’s office. B. At the net bar.
C. At the classroom. D. At home.
2.The underlined sentence in Paragraph 6 may mean .
A. some educators are in favor of students’ using social networking sites
B. some educators can’t block students from accessing social networking sites
C. some educators can’t connect social networking sites easily
D. some educators find it difficult to close social networking sites
3.Which of the following is true according to the passage?
A. The Internet can’t be a good bridge to get along well with students.
B. There are some students threatening other students by using social networking.
C. Most of the misuse of these social web sites takes place at school and affects the home.
D. Too many schools allow students to use social networking sites without Question.
4.What might be the most suitable title for the passage?
A. Lessons Online? B. Friendship Online?
C. Dangers Online? D. Information Online?
If you can find a tree which has been cut down,you will see many rings,or circles,on the base of the trunk.By learning to read these rings,you can find out about the tree's life.
The number of rings tells you how old the tree is.Each year,new wood is formed on the outside of the tree.This new wood is light in color when the tree is growing in spring and summer,and dark in winter when the tree is not growing much.So,if you count the rings of dark?or?light colored wood,you can often find out how old the tree is.
You can also tell which years have been good years and which years have been bad years.When the light?colored rings are very wide,it means that the tree has been growing quickly that year.If the rings are narrow,it has been growing slowly.If the rings on a tree trunk were greatly magnified,you would be able to see why the rings are light?colored when the tree is growing quickly and dark?colored when the tree is growing slowly.The tree trunk is made up of microscopic tubes,like some pipes,carrying water from the soil,through the trunk,and up to the leaves.They are wide and thin?walled when the tree is growing quickly and they are carrying a lot of water.They are narrow and stuck together when the tree is not growing so quickly.
When a tree is old,the tubes in the centre of the tree don't carry water.The walls of the tubes have become thick with materials which have stuck along them over the years,forming a kind of wood called“heartwood”.This kind of wood is darker in color than the young,growing wood on the outside of the tree.
You don't very often see whole tree trunks which have been cut across.But once you learn to read a cross section of the wood,you can see much more in wood which has been used to make boxes,houses and other things.
In most wood,instead of seeing the trunk cut across,you are seeing it cut along its length.Because you don't see the whole tree,you can't tell how old it is.
Title:1.of a Tree
General information | Old trees | ||
Items | Facts | Items | Facts |
Where can rings be seen | On the 2.of a trunk | The tubes in the centre of the tree | Don't carry water |
The3.of rings | Helps us know about its age | The walls of the tubes | Become 4.; Form 5. |
6.light?colored rings | Show the tree grows quickly | ||
Narrow7. rings | Mean the tree grows slowly | ||
Microscopic tubes | Function | Carry8. | |
Features | Wide and 9.when growing quickly | ||
Narrow and stuck together when growing 10. | |||