In Australia, it’s quite usual for people to go camping(露营) during the Easter festival. People can have fun on the grass, on the beach(海滨)or in the woods.

Last Easter holiday, some friends asked me to go camping with them. I was in such a hurry that I took the air bed my brother bought not very long ago without testing(检验) it. The first night at the camping place, I used my friend’s pump(气泵) to blow up the air bed. It didn’t take me long and the new bed looked great. After driving all the way and working hard to put up the tents, we were all very exhausted. As soon as I got my air bed ready, I went back into my tent and went to sleep.

A few hours later, I started feeling the hard ground under my body and my bed didn’t have any air in it. “There must be something wrong,” I thought to myself. However, everyone else was now fast asleep and I didn’t want to wake anyone up at midnight. Then I took out all the clothes and put all of them on the air bed to make it easier for me to fall back to sleep. Luckily, I brought lots of warm clothes and was able to get some sleep for the rest of the night.

The next day, my friend Peter gave me one spare(备用的) air bed. I had a good sleep the other two nights—only some animals came close to my tent and made some noise(噪音).

Our eyesight (视力) is very important to us, so it’s our lifelong job to protect it. The good news is that if we do a few simple (简单的) things every day, we can keep it good easily.

In our everyday life, we can improve and protect our eyesight by eating lots of fresh fruits and vegetables. It is especially (尤其) important for us to eat vegetables like carrots and sweet potatoes. And we need to protect our eyesight when we spend a lot of time in bright sunlight. The best way to do this is by wearing sunglasses that have 100% UV (紫外线) protection. What’s more, we should not spend too much time in front of the computer or television screen (屏幕). That is why doctors advise if we have to use a computer for a long time, we should take a short break every fifteen or thirty minutes.

And it is also important to protect our eyesight when we work with dangerous chemicals. For this reason, we should always wear goggles (护目镜) in chemistry labs at work or at school.

If we do these few simple things, we can protect our eyesight well. As the popular English saying goes, “It’s all fun and game, until someone loses his eyesight”. When people say this, they mean that losing eyesight is a very bad thing.

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When we look at animals, we know that they are not humans (人类). But how do our closest friends—dogs see us?     15     Or do they think that we are just different-looking dogs?

    16     For example, the cuckoo (布谷鸟) will lay (产卵) its eggs in the nest (鸟巢) of another kind of birds. The other birds will feed the baby cuckoos, even though (即使) they look nothing like their babies. This is because feeding little ones is quite natural (自然的) for birds.

Other animals may just divide (划分) the world into animals they eat and animals that eat them.     17    

Sheepdogs leave their mothers when they are born. They grow up with sheep, and come to see them as their family. For this reason, they never attack (攻击) the sheep.     18     They probably think the sheep are dogs, too, but we can’t be certain.

Similarly (类似地), if you raise (饲养) a dog from birth, the way it sees the world will be different from a dog that grows up with other dogs. It may think it is the same kind of animal as you.     19     A Russian boy named Ivan Mishukov, born in 1998, was raised by dogs for two years and came to believe that he was a dog himself.