下列景观代表南方地区的是（ ） A．针叶林 B．落叶阔叶林 C．林海雪原 D．常

在观察草履虫时，为了限制草履虫的运动速度，应在载玻片的培养液上

A．滴加肉汁

B．放少量棉花纤维

C．加少量食盐

D．把水吸干

液压支架乳化液泵常用的柱塞密封为V型密封圈和（）密封圈。

A、O型

B、矩形

C、蕾型

“Old wives’ tales” are beliefs passed down from one generation to another. For example，most of us remember our parents’ telling us to eat more of certain foods or not to do certain things. Is there any truth in these teachings? Some of them agree with present medical thinking，but others have not passed the test of time.

Did your mother ever tell you to eat your carrots because they are good for your eyes? Scientists now report that eating carrots can help prevent a serious eye disease called macular degeneration. Eating just one carrot a day can reduce the possibility of getting this disease by 40%. Garlic is good for you，too. It can kill the type of virus that causes colds.

Unfortunately, not all of Mom’s advice passed the test of medical studies. For example, generations of children have been told not to go swimming within an hour after eating. But research suggests that there is no danger in doing so. Do sweets cause tooth problems？Well, yes and no. Sticky sweets made with grains(谷物) tend to cause more problems than sweets made with simple sugars.

Even though science can tell us that some of our traditional beliefs don’t hold_water,_there is still a lot of truth in the old wives’ tales. After all, much of this knowledge has been accumulated (积累) from thousands of years of experience in family health care. We should respect this body of knowledge even as we search for clear scientific support to prove it true or false.

小题1:Which of the following is TRUE according to the text?

A．Sticky sweets are damaging to our teeth.

B．Eating garlic is good for our eyes.

C．Swimming after a meal is dangerous.

D．Carrots prevent people from catching colds.小题2:The author develops the third paragraph mainly________.

A．by cause and effect

B．by order in space

C．by examples

D．by order in time小题3:The phrase“ hold water” in the last paragraph most probably means“________”．

A．to be valuable

B．to be believable

C．to be admirable

D．to be suitable小题4:What is the author’s attitude towards“old wives’ tales”in the text?

A．Subjective(主观的).

B．Objective(客观的).

C．Dissatisfied.

D．Curious.

某物体沿一直线运动，其v—t图象如图所示，则下列说法中正确的是（）

A.第2s内和第3s内的加速度方向相反

B.第2s内和第3s内速度方向相反

C.第3s内速度方向与加速度方向相反

D.6s末物体距出发点最远

一患者股骨颈骨折术后3周，突发左侧髂窝及股三角区疼痛，左下肢明显肿胀，患肢皮温较对侧高。足背动脉搏动良好。

初步诊断为( )

A．左下肢静脉曲张
B．左下肢深静脉血栓形成
C．左下肢急性动脉血栓形成
D．血栓闭塞性脉管炎
E．腹主动脉瘤