题目内容：

    With all the wars, fighting and sadness in the world today, it's not only necessary, but also essential to have a good sense of humor just to help us get through each and every day of our lives. Putting a smile on someone's face when you know they are feeling down in the dump, makes me feel good and warms my heart.

How would you feel if you could not joke around with your wife, husband, child, co- worker, neighbor, close friends, or even just someone that you are standing in line with at your corner store? I am always saying things that make others smile or laugh, even if I don't know the person I'm joking around with. My Grandma always found humor in everything she did, even if it was the hardest job anyone could imagine. This not only relieves stress in any situation, but also is common courtesy (礼貌) to speak to others that are around you.

I know of a few people that don't have a funny bone in their bodies, as they say. Everyone around them could be rolling on the floor after hearing a great joke and they would sit there without the slightest smile on their face. They don't get the joke that makes others laugh. I am busting a gut while they just sit there, looking at me as if I were from outer space. How can people not get a really funny joke?

Laughing is essential to keep your stress levels under control. Without humor we would find ourselves with a lot of psychological problems, or on a lot of medications to keep us from going crazy. There is too much sadness in this present world. It drives people crazy. We all need to find a way to ignore the sadness and bring a little light into our lives. So，I believe our best medicine is to get together and tell some jokes and have some fun laughing together.

1.According to the author, humor is useful in the aspect that ________.

A.it can pick up people's spirits

B.it makes people more confident

C.it can help people get on well with others

D.it can help get rid of the cruelty in the world

2.From the second paragraph, we can know that ________.

A.the author used to be polite

B.the author's grandma is humorous

C.we should relieve stress in any situation

D.family members should play tricks on each other

3.The underlined phrase ''busting a gut'' in the Paragraph 3 can be replaced by ''________''.

A.explaining carefully B.speaking loud

C.keeping silent D.laughing hard

4.By writing the passage, the author mainly intends to ________.

A.talk about his own understanding of humor

B.encourage people to be humorous in daily life

C.introduce a practical way to get through daily life

D.convince people of the power of being optimistic about life

5.What is the author's attitude towards the present world according to the last paragraph?

A.Satisfied. B.Positive.

C.Critical. D.Indifferent.