电子控制燃油喷射系统有哪些优点？_爱下问搜题

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问题问答题简答题

电子控制燃油喷射系统有哪些优点？

答案

参考答案：

1.能提高发动机的最大功率

2.耗油量低，经济性能好

3.减小了排放污染

4.改善了发动机的低温起动性能

5.怠速平稳，工况过渡圆滑，工作可靠，灵敏度高

完形填空

A man who knows how to write a personal letter has a very powerful tool. A letter can be enjoyed, read and   36 . It can set up a warm conversation between two people far apart (远离的);it can keep a   37  with very little effort.
I will give   38 .A few years ago my older brother and l were not getting   39 .We had been close as    40   but had grown apart. Our meetings were not   41 ; our conversation was filled with arguments and quarrels: and every effort to clear the air seemed to only   42  our misunderstanding. Then he   43  a small island in the Caribbean and we   44  touch. One day he wrote me a letter. He described his island and its people, told me what he was doing, said how he felt, and encouraged me to   45 . Rereading the letter, I was   46  by its humor（幽默）and clever expressions. These were all qualities for which I had   47  respected my older brother but   48  he no longer had them. I had never known he could write so 49 . And with that one letter we became friends   50 .
It might never have occurred to   51  to write me if he had not been in a place where there were no   52 . For him, writing was a necessity. It also turned out to be the best way for us to get back in touch. Because we live in an age of 53  communication（通讯）, people often   54  that they don’t always have to phone or email. They have a  55  . And that is to write.

C．an experience

A．mail services

B．transport services

单项选择题

醛一般表达式可写为（）

A.RCOOR′

B.ROR′

C.RCOR′

D.RNH₂

E.RCHO