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问题 选择题

下列说法正确的是

A．物体运动状态发生改变，一定受到力的作用

B．物体的运动状态不发生改变，一定没有受到力的作用。

C．力的作用效果只由力的大小决定

D．物体受力后一定同时出现形变和运动状态的变化。

答案

A

题目分析:力是改变物体运动状态的原因，所以A对；物体的运动状态不发生改变，有可能受到平衡力的作用，所以B、D错；力是矢量，力的作用效果不只是由力的大小来决定的，与方向也有关的，所以C错；

单项选择题

Anyone who doubts that children are born with a healthy amount of ambition need spend only a few minutes with a baby eagerly learning to walk or a headp toddler starting to talk. No matter how many times the little ones stumble in their initial efforts, most keep on trying, determined to master their amazing new skill. It is only several years later, around the start of middle or junior high school, many psychologists and teachers agree, that a good number of kids seem to lose their natural drive to succeed and end up joining the ranks of underachievers. For the parents of such kids, whose own ambition is often inseparately tied to their children’s success, it can be a bewildering, painful experience. So it is no wonder some parents find themselves hoping that ambition can be taught like any other subject at school.
It’s not quite that simple. "Kids can be given the opportunities, but they can’t be forced," says Jaequelynne Eccles, a psychology professor at the University of Michigan who led a study examining what motivated first-and-seventh-graders in three school districts. Even so, a growing number of educators and psychologists do believe it is possible to unearth ambition in students who don’t seem to have much. They say that by instilling confidence, encouraging some risk taking, being accepting of failure and expanding the areas in which children may be successful, both parents and teachers can reignite that innate desire to achieve.
Dubbed Brainology, the unorthodox approach uses basic neuroscience to teach kids how the brain works and how it can continue to develop throughout life. The message is that everything is within the kids’ control, that their intelligence is

malleable

.
Some experts say our education system, with its p emphasis on testing and rigid separation of students into different levels of ability, also bears blame for the disappearance of drive in some kids. Some educators say it’s important to expose kids to a world beyond homework and tests, through volunteer work, sports, hobbies and other extracurricular activities. "The crux of the issue is that many students experience education as irrelevant to their life goals and ambitions," says Michael Nakkula, a Harvard education professor who runs a Boston-area mentoring program called Project IF (Inventing the Future), which works to get low-income underachievers in touch with their aspirations. The key to getting kids to aim higher at school is to tell them the notion that classwork is irrelevant is not true, to show them how doing well at school can actually help them fulfill their dreams beyond it. Like any ambitious toddler, they need to understand that they have to learn to walk before they can run.

The word "reignite" underlined in Paragraph 2 is closest in meaning to ______.

A．rekindle

B．confirm

C．find out

D．strike
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单项选择题

燃气工程的施工组织设计，根据（）情况基本上可分为施工组织总设计，施工组织设计，施工方案及专项技术措施几种。

A、施工

B、技

C、任务

D、流程
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