修复前正畸治疗主要包括（）. A.开拓失牙间隙，调整牙齿位置 B.竖直倾斜基牙，集中

有13盒糖果，其中12盒质量相同，另有一盒少了几颗糖，如果用天平称，至少几次可以找出这盒糖果？请写出过程．

乒乓球运动是集竞技、娱乐、健身于一体的体育运动，如图所示。为了备战第30届伦敦奥运会，国手王浩在球场内苦练本领，他在击球过程中用到了哪些物理知识?

①球拍表面贴橡胶： 　　　(增大/减小)球与球拍间的摩擦

②弧圈球（旋转的球沿弧线运动）：　　　　   

③球拍将球击扁，使乒乓球存储了            

WASHINGTON --- It’s a great achievement that inspires concepts of robots with consciousness and independent minds.

When people or animals get hurt, they can usually compensate for minor injuries and keep limping along, but for robots, even slight damage can make them stumble and fall. However, a recently made robot has demonstrated a new ability: it can heal its own damage.

The new robot, which looks like a splay-legged (弓形腿的), four-footed starfish, can sense injury to itself and adapt. That ability sets the new robot apart from earlier machines. Because the robot can recover from unfamiliar places.

“There is a need for planetary robotic rovers (行星机器探测车) to be able to fix things on their own,” says Josh Bongard, a professor in the University of Vermont, who is one of the device’s creator. “Robots on other planets must be able to continue their mission without human help if they are damaged and cannot communicate their problem back to Earth.”

A typical robot functions according to a computer program, but the new robot works differently. First, sensors in its four legs observe the robot’s movements and signals to its built-in computer. From the information it collects, the robot creates its own programs that allow it to adapt to different situations. For example, when the researchers shortened one of the robot’s legs, the smart machine simply adjusted its way of walking—it used three legs instead of four.

The researchers are looking for other places to put the resilient robot to work. One spot is the ocean floor. That dark and dangerous undersea area might be a good choice for a robot that the scientists call the Starfish. “We never officially named the robot, but we usually refer to it as the Starfish, even though a real starfish has five rather than four legs,” says Bongard. “Also, a real starfish is much better than our robot at recovering from injury, because it can actually grow its legs again.” Scientists have created robots that help humans in many ways: by exploring space, fighting fires, and even performing surgery.

小题1:The newly designed robot distinguishes itself from the former ones because it________.

A．can communicate with people on the earth about their problems

B．works according to a certain computer program

C．can find its problems and solve them automatically

D．can explore unfamiliar places小题2:An example is given in the fourth paragraph in order to explain that the robot ________.

A．is used to create new programs

B．has typical robot functions

C．has sensors to observe its movements

D．can gather information and adapt to new conditions小题3:Which of the following is TRUE about the robot “Starfish”?

A．It was spoken highly of by people for its special ability.

B．It will stumble and fall if damaged.

C．It can grow its legs again once they are broken.

D．It has started to work on the ocean floor.小题4:What might be the best title of the passage?

A．How the Starfish Robot Works

B．Do-It-Yourself Robot Repair

C．Robots Designed to Work on Other Planets

D．New Robot Helping Us in Many Ways

结构中具有两个手性中心的药物是

A．青霉素钠

B．氨苄西林

C．头孢氨苄

D．土霉素

E．氯霉素

When a Shanghai ad consultant was recently asked to recommend young local designers to an international agency, he sent three candidates with years of work experience. But the company decided they weren’t good enough and had to import designers from the West. It’s a common problem that Chinese vocational grads simply haven’t had good enough teaching. Most of the lecturers don’t have any real work experience, so they can’t teach useful things. When graduates do get hired, they basically have to be re-educated.

China’s rapid economic expansion has exposed many frailties in its education system, especially on the vocational side. The country can’t produce enough skilled workers. In part that’s because it invests far more in academic than vocational programs. Funding has fallen significantly since the 1990s. Partly as a result, today only 38 percent or so of China’s high-school-age students attend vocational schools, well below the official target of 50 percent. To address this deficit, last year Beijing pledged to spend almost $2 billion on 100 new vocational colleges and 1,000 high schools. And this year it started offering annual subsidies to vocational students.

But China’s training is too abstract, what’s urgently required are technicians who can come up with a good idea and turn it into a marketable product. Parts of the country are already adapting; in Shenzhen, local institutes offer" made to order" training for particular businesses. And some vocational colleges have introduced practical research projects.

But vocational education faces a deeper problem: its image. China’s middle class is eager to forget its experience with physical labor, and few allow their children to become technical workers. Everyone thinks these are things that low-class people do. Thus China now produces record numbers of college grads--who struggle to find work because they lack the skills for manufacturing, where demand is greatest. One fix would be to re-brand vocational subjects as" professional," not" manual," skills.

At the other end of the spectrum are China’s 100 million-plus rural migrant workers, many of whom have little schooling. They have never learned how to work with others, to live in the city, save money or choose the right job. Thus they find it hard to learn from their jobs or plan their careers. This results in extremely high labor turnover. Teaching and training" life skills" to complement vocational programs would help.

Yet the urgency of China’s skilled-labor shortfall will force a rethink. For now, China is relying on cheap, low-skilled, labor-intensive production, but it’s not sustainable in the long term, We must raise our skills level, and it’s impossible for state-run colleges to do all the training. Indeed, with the demand for skilled workers growing all the time, China will need all the help it can get.

According to the text, a lower rate of school-aged teenagers enter vocational schools in China mainly because （）

A.the vocational education lacks government financial support

B.the public do not think much of the vocational workers

C.few allow their children to become technical workers

D.they fear that they can not find a job after graduation