问题 选择题

已知等腰三角形一腰上的高线等于腰长的一半,那么这个等腰三角形的一个底角等于(  )

A.150或750

B.150

C.750

D.1500和300

答案

答案:A

题目分析:此题有两种情况,一种是该高线在等腰三角形内部,另外一种是在等腰三角形外部。当该高线在三角形内部时,那么该三角形的顶角度数为300,其底角也就是为750。当高线在三角形外部时,其顶角度数为1500,那么其底角为150

点评:此题有一定的难度。考生容易忽视两种情况,只考虑到一种情况。此类型题经常出现在各种试卷上,希望考生能通过此题达到举一反三的效果。

阅读理解

阅读短文,根据意思,判断所给句子的正误。正确的写T,错误的写F。

“How are you?” is a nice question. It’s a friendly way that people in the U.S.A greet(问候) each other. But “How are you?” is also a very unusual(不寻常的) question. It’s a question that often doesn’t need an answer. The person who asks“ How are you?” hopes to hear the answer “Fine”, even if the person’s friend isn’t fine. The reason is that “How are you?” isn’t really a question and “Fine” isn’t really an answer. They are simply (只)other ways of saying “Hello” or “Hi”.

  Sometimes, people also don’t say exactly(确切) what they mean. For example, when someone asks “Do you agree?”, the other person might think, “No, I disagree. I think you’re wrong...”But it isn’t very polite to disagree so strongly(强烈地), so the other person might say “I’m not sure.” It’s a nicer way to say that you don’t agree with someone.

  People also don’t say exactly what they are thinking when they finish talking with other people.For example, many talks on the phone finish when one person say “I’ve to go now.” Often, the person who wants to hang up(挂)says: “Someone’s at the door.” “Something is burning (烧)on the stove(炉).” The excuses(借口) might be real(真的), or not. Perhaps the person who wants to hang up simply doesn’t want to talk any more, but it isn’t polite to say that. The excuse is more polite, and it doesn’t hurt (伤)the other person.

  Whether they are greeting each other, talking about an idea, of finishing a talk, people don’t say exactly that they are thinking. It’s an important way that people try to be nice to each other, and it’s part of the game of language.

小题1:“How are you?” is another way of saying "Hello." or" Hi."

小题2:It is polite to say" No. I disagree. I think you are wrong, "if you don’t agree with others.

小题3:When someone says "I have to go now "On the phone,it means he wants to go on talking.

小题4:"Someone is at the door." may be an excuse for finishing a talk.

小题5:Sometimes people don't say exactly what they are thinking about just because they try to be nice to each other.

单项选择题