问题 问答题 简答题

简述RAD调速器怠速工况的工作过程。

答案

参考答案:

飞块离心力与怠速弹簧及起动弹簧的合力平衡时,供油齿杆保持在一定位置,发动机在相应的怠速下稳定工作。若外界阻力增加使转速下降,滑套在怠速弹簧与起动弹簧合力作用下,带动导动杠杆和浮动杠杆,供油齿杆向增油方向移动转速上升,直至飞块离心力与起动弹簧和怠速弹簧合力重新达到平衡为止,反之亦然,从而使怠速稳定。

问答题 论述题
完形填空

.

Section D

Directions: Read the passage carefully and answer the questions or complete the statements in the fewest possible words.

  Many parents who welcome the idea of turning off the TV and spending more time with the family are still worried that without TV they would constantly be on call as entertainers for their children. They remember thinking up all sorts of things to do when they were kids. But their own kids seem different, less creative, somehow. When there’s nothing to do, these parents observe regretfully, their kids seem unable to come up with anything to do besides turning on the TV.

  One father, for example, says, “When I was a kid, we were always thinking up things to do, projects and games. We certainly never complained in an annoying way to our parents, ‘I have nothing to do!’” He compares this with his own children today: “They’re simply lazy. If someone doesn’t entertain them, they’ll happily sit there watching TV all day.”

  There is one word for this father’s disappointment: unfair. It is as if he were disappointed in them for not reading Greek though they have never studied the language. He deplores(哀叹) his children’s lack of inventiveness, as if the ability to play were something innate(天生的) that his children are missing. In fact, while the tendency to play is built into the human species, the actual ability to play — to imagine, to invent, to elaborate (描述) on reality in a playful way — and the ability to gain fulfillment from it, these are skills that have to be learned and developed.

  Such disappointment, however, is not only unjust, it is also destructive. Sensing their parents’ disappointment, children come to believe that they are, indeed, lacking something, and that this makes them less worthy of admiration and respect. Giving children the opportunity to develop new resources, to enlarge their horizons and discover the pleasures of doing things on their own is, on the other hand, a way to help children develop a confident feeling about themselves as capable and interesting people.

81. According to many parents, without TV, their children would ask them to ___________.

___________________________________________________________________________

82. Why is it unfair for the father to blame his children for not being able to entertain themselves?

___________________________________________________________________________

83. When parents show constant disappointment in their children, the destructive effect is that the children will___________.

___________________________________________________________________________

84. According to the author, in what way can children’s self-confidence be developed?

___________________________________________________________________________