题目

如图所示，灯L1和L2是两只相同的灯泡，a、b是电流表或电压表。闭合开关S后，两灯都能发光，则下列判断正确的是A. a、b均为电流表 B. a、b均为电压表C. a为电流表，b为电压表 D. a为电压表，b为电流表 答案：C 【解析】 如果两个灯泡串联,无论a、b是什么仪表,L2都会被短路,故电路不可能为串联;那么两个灯泡的连接方式一定为并联,所以为了使灯L1、L2正确发光，a处相当于导线，即电流表；b处不能形成通路，否则会形成电源短路，故b处为电压表。故选C.Good manners play an important part in maintaining（保持）peace in society. A man with good manners doesn’t hurt others’ feelings, and therefore he’s on good terms with everyone. In this way he helps to keep the peace in society.But a man with bad manners has no respect for others. He uses words carelessly and behaves rudely towards others and causes a lot of unpleasantness. In the end, he himself will suffer the most. Everyone avoids him and he is forced to live alone.To live well in society, money alone is not enough. Even the richest man cannot afford to have bad manners. He may have enough money to buy all things he wants; but if his manners are bad, he will have no friends, and no one can live happily without friends.We should have good manners, for it’s human nature to try to get friendship; and friendship has to be earned （获得）through our own attitude towards others. If we are kind to others, they will be kind to us, and kindness is the most basic quality of good manners. Bad manners drive away friends as well as our own family members.On the other hand, a man with good manners has many friends. He commands the respect of all those who come into contact（联系）with him. He doesn’t talk ill about others. Even when he’s provoked, he tries his best not to upset others. He also feels sorry about the weak and the disabled.There are, however, many people who behave so well outside their homes that they are respected by everyone outside. But in their own homes they are worse than the devil（魔鬼）. Such people cannot be said to have good manners. Their behavior will soon be discovered by others.If one’s manners are good, one behaves well everywhere, even when one is away from the critical（爱挑剔的）eyes of others. Only such a person can live well in society.1.People with good manners bring society _____.A.peaceB.enjoymentC.respectD.friendship2.What does the author mainly want to tell us in Paragraph 4 ?A.People are born friendly.B.Bad manners make people lose friends.C.Money is not the most important.D.Kind people will be treated kindly.3.The underlined word “provoked” in the passage may mean _____.A.tiredB.sad C.made angryD.left alone4.What’s the main idea of the passage ?A.Kindness is important.B.Friendship is important.C.Good manners are important.D.People with bad manners can’t live well.