正常成年人脑脊液中白细胞计数参考值为（） A.（5～20）×106／L B.（0～1

阅读理解。

     Once there was a boy. He loved sweets very much.  He always asked his father for sweets.

     The boy's father thought hard about how to stop the child from asking for so many sweets. A great

man lived nearby. The boy's father decided to take the boy to him.  He might be able to make the child

give up sweets.

     So they went to the great man. The father asked the great man to help him. But the great man liked

sweets himself. He told the father to bring his son back after a month.  

     During the month, the great man tried to give up eating sweets. At last he did it. When the boy and his

father returned after a month, the great man had a talk with the boy. From then on, the boy didn't ask for

sweets anymore.

     The boy's father felt surprised, "Why didn't you ask my son to give up sweets when we came to you

a month ago?" The man answered, "How could I ask a boy to give up sweets when I loved sweets

myself? In the last month I gave up eating sweets. "

     A person's example is always stronger than words. We should not ask others to do what we can't do

ourselves.

根据短文内容，下列问题。

1. What did the boy love very much?

2. Who did the boy's father decide to ask for help?

3. How long did it take the great man himself to give up eating sweets ?

4. Did the great man help the boy give up the sweets at last? ' 

5. What can we learn from the story?

如图是某粒子的结构示意图．

（1）若该粒子为钠离子，则m=______；

（2）若该粒子为原子时，则m______x+2（选填“＞”“＜”或“=”），若m=3x，则该元素属于______元素（填“金属”或“非金属”）．

患者．男性，29岁，右下腹痛，腹泻2年，无粘液脓血便.

X线钡餐灌肠示回肠末端呈线样征。提问：诊断何种疾病（）。

A.肠结核

B.溃疡性结肠炎

C.非特异性炎症

D.Crhon病

E.阿米巴痢疾

在聚酰胺色谱上对黄酮类化合物洗脱能力最弱的溶剂是

A．95%乙醇

B．丙酮

C．水

D．甲酰胺

E．碱水

蒸汽通过喷嘴，超声速流动时，气流截面（）。

A.收缩

B.缩至最小

C.扩张

D.以上都不正确