钢梁杆件弯曲的检查办法,是用弦线测出弯曲各点的()。
A、周围的锈蚀面积
B、矢矩
C、裂纹的宽度
D、拱度
参考答案:B
New rules and behavior standards(行为规范) for middle school students came out in March. The Middle School is going to use a new way to decide who the top students are. The best students won’t only have high marks. They should not (染) their hair, smoke or drink because they are students. The following are some of the new rules. Have you ever copied someone else’s work in an exam Don’t do that again! That’s not something an honest student should do. Do more at school. Good students love animals and care for other people. April is Bird-loving Month in China. Is your school doing anything to celebrate it You should join! And you can learn more about animals and how to protect them. Be friendly to the people around you. Try to think of others, not only yourself. Be open to new ideas. Do you think people can live on the moon7 Maybe you’ll find another earth someday. Don’t look down on new ideas. Everyone’s ideas are important. You should welcome them, because new ideas make life better for everyone. Protect yourself. Has someone ever taken money from one of your classmates Don’t let it happen to you. If you have to go home late, you should let your parents know. Use the Internet carefully. The Internet can be very useful for students. But some things on the Internet aren’t for children, so try to look at web pages (网页) that are good for you.
The passage mainly(主要地) tells us how to ______.
A.care for others
B.do more at school
C.be top students
D.use the Internet
单边带无线电话与调幅电话相比,主要优点是()。
A、占用频带窄
B、解调方便
C、话音清晰
D、频道转换时间短