如图所示，质量为m的木块在水平面上的木板上向左滑行，滑行时木板静止，木板质量M=

______ do you call your mother's sister in English?         [ ]

A. How      

B. When      

C. Why      

D. What

试述病毒和细菌人工培养的主要不同点。

In a great many cities, hundreds of people ride bikes to work every day. In New York, some bike riders have even formed a group called Bike for a Better City. They declare that if more people rode bikes to work, there would be fewer automobiles in the downtown part of the city and so less dirty air form car engines.

For several years, this group had been trying to get the city government to help bike riders. For example, they want the city to draw special lanes(车道) for bikes on some of the main streets, because when bike riders must use the same lanes as cars there are accidents. Bike for a Better City feels that if there were special lanes, more people would use bikes.

But no bike lanes have been drawn. Not everyone thinks it is a good idea—they say it will slow traffic. Some store owners on the main streets don’t like the idea—they say that if there is less traffic, they will have less business.

The city government has not yet decided what to do. It wants to keep everyone happy. On weekends, Central Park—the largest place open ground in New York— is closed to cars, and the roads may be used by bikes only.

小题1:In New York, a group of bike riders__________.

A．are keeping practicing for health

B．have no cars of their own

C．are complaining there are not enough buses

D．are trying to settle the problem of air pollution小题2: The bike riders suggest that __________.

A．bikes should be used instead of cars

B．bike lanes should be drawn

C．fewer buses or cars should be used

D．the number of special lanes should be decreased小题3:The advantage of the special lanes is that__________.

A．they will make cars and buses run slowly

B．they will make it easier for bike riders to go to parks

C．they will make the city more beautiful

D．they will prevent accidents

甲苯和二甲苯主要毒性表现

A．消化系统毒性

B．内分泌毒性

C．皮肤毒性

D．肾毒性

E．中枢神经系统毒性

某女，52岁。患过敏性鼻炎已近10年，每遇气温变化即鼻塞流清涕，喷嚏不断，平素怕冷，面色白，气短、自汗，舌淡苔白，脉沉细。临床诊断最可能是（）。

A．肾阳虚证

B．肺气虚证

C．肺肾气虚证

D．风寒犯肺证

E．以上全都不是