等价划分技术是设计方案的一种 【5】 。

In northern China during spring, big sandstorm often make trouble for people. Sandstorms usually happen in spring. They have happened in more than 10 provinces in northern China this year. People in southern China don’t have to worry about this kind of bad weather. Most of the sand comes from the north of China. In northern China, lots of places have few trees and don’t get much rain. When there aren’t many trees, the ground can’t keep enough water. Over the years, the ground dries up and turns to sand. When spring comes and the ice melts, the ground becomes loose. Strong winds take the loose sand into the sky. Besides, in northeast China, there lies some vast deserts.

Sandstorms are bad for people’s health. If people breathe in too much sand, they will cough or have serious illnesses. Sandstorms also give farmers lots of problems. Sometimes their sheep get lost in the storms and never come back home. The winds also tear the farmers’ houses down.

What can you do to stop sandstorms? Here’s a piece of advice. Ask your parents to help you plant some trees this spring. If you see people cutting down too many trees, tell them about the dangers of sandstorms, and ask your government to stop them.

小题1:When do sandstorms usually happen?

A．In summer.

B．In spring.

C．In winter.

D．In autumn小题2:What does the underlined word "loose" mean in China?

肥沃的           B.贫瘠的        C.疏松的        D.大量的

小题3:The second paragraph tells us ______________.

A．why sandstorms happen in northern China

B．the dangers of sandstorms

C．sandstorms aren’t terrible at all

D．how sandstorms happen小题4:Which of the following is NOT a way to stop sandstorms?

A．Plant more trees in spring.

B．Stop people to cut down too many trees

C．Don’t stay outside when sandstorms happen.

D．Tell people about the dangers of sandstorms.小题5:Which is the best title for this passage?___________

A．Sandstorms

B．How we can stop sandstorms

C．Why sandstorms only happen in northern China.

D．Sandstorms can influence most of China.

When Mary was young, she ________ able to dance very well.            [ ]

A. could be    

B. can be      

C. was         

D. could

血浆置换术适应征有

A．中毒症

B．高粘滞综合征

C．格林－巴利综合症

D．以上均是

男，26岁，间歇性头痛，CT检查，最可能的诊断为（）

A.胆脂瘤 

B.蛛网膜囊肿 

C.脑软化灶 

D.脑梗死 

E.脑囊肿 

奥苏贝尔认为影响迁移的认知结构变量包括（　）

A．可利用性

B．变通性

C．可辨别性

D．适应性

E．稳定性