题目内容
Natural ways of keeping time
In ancient times, people had to use the sun and the moon to tell time. They got up when the sun came up and worked in the fields until the sun went down.
Man-made things
The sand clock is made of two glass balls joined by a narrow neck. The top ball was filled with sand. The sand slowly moved through the neck into the bottom ball. People knew how much time had passed when all the sand had fallen to the bottom ball.
People also made the water clock. They made a small hole near the bottom of a pot. Then they filled the pot with water. Markings inside the pot showed how much time passed as the water dripped (滴) out of the hole.
Nature’s Clocks in Living Things
◆Animals’ Body Clock
Animals do not need clocks to know time. They have a way of telling time by their bodies. Birds know when to fly to warmer places before winter. Some animals know when to keep more food for the cold winter months. Some fish know when it is time to move up the river and lay eggs.
◆Plants have their own clocks
Plants also have their own clocks to keep time. Plants know when to open flowers or when to drop their leaves.
◆The Body Clock in Human Beings
People also have their own body clocks. When we get used to our lives, our body clocks can be very accurate (准确的). It can tell us when it is time to wake up. It can also tell us when to eat or to go to sleep.
【小题1】How could an ancient farmer know when to go back home in the daytime?
A.By looking at the moon. | B.By looking at the stars. |
C.By looking at the sun. | D.By feeling whether tired or not. |
A.2. | B.3. | C.5 | D.6. |
A.both of them have a hole. | B.both of them are designed with glass balls. |
C.both of them can be used only once. | D.both of them tell time in the same way |
【小题1】C
【小题2】B
【小题3】D
解析
Many of us don't pay much attention to the importance of eye care. It is said that if you take care of your body, then you can surely be healthy. That is why our eyes should be given a lot of care. Natural eye care should be put in a number one place.
There are several causes leading to poor eyesight like not enough food, genes (基因) and aging (老化). Televisions, computers and reading are also the causes of having poor eyesight. If you happen to work in front of the computer, it is best to take a break every once in a while. Something dirty can cause redness and they will make you feel uncomfortable. It is bad for your eyes, too. If this happens, the best way is to clean your eyes by using cold water. You must also try your best to protect your eyes from harmful things. For example, sunglasses are not just for fashion but they can also serve as a great way to protect your eyesight form UV rays.
Eating healthy foods will do good to your eyesight. Remember that vitamins A, C and E are good for eyes. Try to eat food groups that have these vitamins. And you should do eye exercises because exercise protects your eyesight, too. If a person exercises regularly (定期地) and eats the right kind of food, his eyes will stay in good condition for a long time.
All above are natural ways of eye care that help us keep healthy eyes. Being happy all the time can be helpful to a person's eyesight, too. In a word, eye care is very important, no matter how old a person is.
【小题1】_____ is the most important way to protect our eyes.
A.Seeing the doctor | B.Taking medicine |
C.Natural eye care | D.Being happy all the time |
A.age | B.height | C.reading | D.computers |
A.Eat healthy foods. | B.Have a rest after working for a while. |
C.Wear a pair of sunglasses. | D.Clean the eye by using cold water |
A.Ways of Being Happy | B.Ways of Eye Exercises |
C.Ways of Eye Care | D.Ways of Being Healthy |