题干

已知不重合的两直线l1l2对应的斜率分别为k1k2,则“k1=k2”是“l1l2”的(   )

A:充分不必要条件

B:必要不充分条件

C:充要条件

D:既不是充分也不是必要条件

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A

同类题2

阅读理解

    When you meet someone for the first time, you will get a quick idea in your mind of that person in the first moment. Your feelings about other people, however, are really just show the way that you look at yourself.

    So you can allow others to be the mirror to see your own feelings of self-worth more clearly. And, you can see the people you don't like as mirrors to show you what you are not accepting about yourself.

    To live peacefully with others, you will need to learn patience. A big challenge is to let your judgment of others be a lifelong research of yourself. Your task is to consider all the judgments you make onto others carefully and to begin to see whether you can use them to help yourself to become better.

    Several days ago I had a business lunch with a man who showed objectionable table manners. My first feeling was that he was impolite. When I noticed that I was judging him, I stopped and asked myself what I was feeling. I discovered that I was nervous to be seen with someone who was eating with his mouth open.I was very surprised to find how much I cared about how the other people in the restaurant judged me.

    Remember that your judgment of someone will not stop you from becoming like him. Just because I think my lunch partner impolite, it does not prevent me from looking or acting like him. In the same way, my patience to him would not make me eat food with my mouth open.

    When you get close to life in this way, those whom you hate and those whom you love can be seen as mirrors, guiding you to discover parts of yourself that you dislike and to accept your greatest personalities you are proud of.

同类题4

阅读理解

    Getting rid of dirt(灰尘), in the opinion of most people, is a good thing. However, there is nothing fixed about attitudes to dirt.

    In the early 16th century, people thought that dirt on the skin was a way to block out disease, as medical opinion had it that washing off dirt with hot water could open up the skin and let illnesses in. A particular danger was thought to lie in public baths. By 1538, the French king bad closed the bath houses in his kingdom. So did the king of England in 1546. Thus it began a long time when the rich and the poor in Europe lived with dirt in a friendly way. Henry IV, King of France, was famously dirty. Upon learning that a nobleman had taken bath, the king ordered that, to avoid the attack of disease, the nobleman should not go out.

    Though the belief in the merit of dirt was long-lived, dirt has no longer been regarded as a nice neighbor ever since the 18th century. Scientically speaking, cleaning away dirt is good to health. Clean water supply and hand washing are practical means of preventing disease. Yet, it seems that standards of cleanliness have moved beyond science since World War ll. Advertisements repeatedly sell the idea: clothes need to be whiter than white, cloths ever softer, surfaces to shine. Has the hate for dirt, however, gone too far?

    Attitudes to dirt still differ hugely nowadays. Many first-time parents nervously try to warm(警告)their children of touching dirt, which might be responsible for the spread of disease. On the contrary, Mary Ruebush, an American immunologist(免疫学家), encourages children to play in the dirt to build up a strong immune system. And the latter position is gaining some ground.