It is easy for us to tell who our family members are, but do plants recognize(识别) their own family? Some do, scientists say, according to a report by Science News in early 2010.
Guillermo P. Murphy and Susan Dudley are two plant scientists from McMaster University in Hamilton, Canada. They did a few experiments with Jewelweeds, a kind of flower that grows in wet, shady spots. They found that the flowers seem to know their own flower family. In their experiments, Murphy and Dudley planted jewelweeds in pots with either siblings or strangers.
When jewelweeds were planted in pots with strangers, the plants started to grow more leaves than if they had been planted alone. This response(反应)suggests that plants are competing with strangers for sunlight, since a plant with more leaves can receive more light and make more food. Jewelweeds usually grow in the shade, where sunlight is not enough.
When jewelweed seedlings(幼苗)were planted with siblings, they grew a few more branches than they usually would if they were alone – but they did not start growing lots of extra leaves. This behavior suggests the plants are more likely to share resources, rather than compete.
According to the Science News report, Jewelweeds are not the first plants that plant scientists have studied for family recognition. In 2007, Dudley and her team studied the Great Lakes sea rocket, a plant that grows on the beach – where it may be hard to get fresh water. In that experiment, the scientists found that when sea rockets were planted with siblings, they tolerated each other. But when they were planted with strangers, the sea rockets reacted by working extra hard to grow lots of roots.
Dudley says this just because sea rockets, on the beach, get plenty of sun but struggle for water – so when they’re threatened, they compete for water. Jewelweeds have plenty of water but have to compete for sunshine, so they grow more leaves. What does the underlined word siblings mean?
| A．Flowers come from foreign countries. |
| B．Plants growing in different environments. |
| C．Flowers planted with lots of strangers. |
| D．Plants that are the same kind. |
In the text, the writer mentioned the experiments of Jewelweeds to .
| A．make a comparison | B．introduce a topic |
| C．describe a pretty flower | D．build a new theory |
According to the passage, flowers planted alone will .
| A．grow more leaves than those planted in groups |
| B．become taller than those with more branches |
| C．grow fewer leaves than those planted with strangers |
| D．become ill easily because they can’t get enough shade |
What can be the best title for the passage?
| A．New Discoveries about Plants |
| B．How Plants Compete with Each Other |
| C．Family Recognition among Plants |
| D．Jewelweeds and the Great Lakes Sea Rockets |
A punctual person is in the habit of doing a thing at the correct time and is never late for anything.
An unpunctual man never does what he has to do at the right time. He is always in a hurry and in the end loses both time and his good name. A lost thing may be found again, but lost time can never be got back. Time is more useful than material things. In fact, time is life itself. An unpunctual man is always wasting his most important things as well as others'. An unpunctual person is always saying unhappily that he finds no time to answer letters or return calls. But the man who really has much to do is very careful of his time. He knows that he can not finish all his work unless he carefully does every piece of work.
Being unpunctual is the sign of disrespect (不尊重_) towards others. If a person is invited to
dinner and arrives later than the time when he should be there, he keeps all the other guests (客人)
waiting for him. Usually this will be thought as a great disrespect to the host and all the other guests.
Not like a punctual person, an unpunctual one can't do his duty wonderfully, whether it is public or personal. Imagine how it would be if those who should do important tasks failed to be on time. A man who is known to be often unpunctual is never believed by his friends or fellow men.The Chinese meaning of the word "punctual" in this passage is probably “ ”.
| A．听话的 | B．守时的 | C．守纪律的 | D．能干的 |
Which of the following is TRUE according to the passage?
| A．An unpunctual person often has more time. |
| B．An unpunctual person has more work to do. |
| C．A punctual person often has a busy life. |
| D．A punctual person often does his work wonderfully. |
When you are invited to dinner, you'd better arrive there .
| A．in a hurry | B．after the host |
| C．at the decided time | D．before other guests |
From the passage, we learn that an unpunctual man usually in the end.
| A．saves time for others |
| B．leaves his family and friends |
| C．gets his chances and knowledge |
| D．loses his time and good name |
A school bus is one that is used to take children to and from school.
In the USA, about 450,000 school buses take more than 25 million children to and from school. The yellow school bus is a US icon (象征). Yellow became the color of school buses in the USA in 1939. Dr. Frank got the good idea. He said it was easy for people to see yellow buses and the black letters on them in early morning or late afternoon. That would make children safer.
There are not many school buses in Britain, and they are not yellow. They have trackers (追踪器) on them, so kids are being tracked while they travel to and from school by bus. The trackers let parents know where the school bus is and whether their kids are on the bus.
Kindergarten (幼儿园) is a difficult time for some kids. It's the first time for them to go away from their parents. To make kids love their school, Japanese kindergartens and schools have colorful buses. The buses can easily make children want to take them--and then, go to school. Even some parents want to take them, too!
School buses are becoming more and more popular in China now. It saves a lot of time for students to take a school bus. It's said that there will be 3,000 yellow school buses on the road by the end of this year in Chongqing.According to Dr. Frank, school buses are safer for the students.
| A．yellow | B．black | C．white | D．colorful |
Children in Japan may easily by taking the school bus.
| A．save time | B．love their school |
| C．play games | D．do their homework |
Chinese students will save a lot of time to to school.
| A．walk | B．take a taxi |
| C．ride a bike | D．take a school bus |
This passage is mainly about .
| A．school buses | B．school life |
| C．popular colors | D．students' safety |
If you want to work as a taxi driver, you can call .
| A．555-7296 | B．555-6238 | C．555-7843 | D．555-9767 |
lost a small, black and white dog.
| A．Mark | B．Zig Zag | C．Mr. Winter | D．Gus. Reward |
If Mrs. White wants to see Titanic 3D with her 10-year-old daughter, she will pay dollars.
| A．10 | B．20 | C．30 | D．32 |
I was quite close to my grandmother, Julia. We lived with her and then she lived with us. She was a very nice person, both kind and patient. She taught me to read and write when I was young and helped me to be interested in stories and poems.
In my mind, my grandmother was a great tailor. She made clothes or toys better than anything you can buy in a shop today. She always made clothes for family and friends.
My grandmother was also a hard worker both at home and at work. I can still remember the difficult time when we were very poor. At that time, my grandmother was already sixty years old but she worked in a hospital for a long time every day--not in the office but doing the cleaning outside and taking care of me at the same time while my mom was at work!
My brother and sisters also love her. We will never forget our grandmother. She is really important in our lives and is always there for all of us in one way or another. I am proud to be her grandson.The writer's grandmother taught him to when he was young.
| A．read and write | B．sing and dance |
| C．draw and sing | D．play and learn |
His grandmother always made for family and friends.
| A．cakes | B．cards | C．meals | D．clothes |
While his mom was , his grandmother took care of him.
| A．at home | B．at work | C．out of work | D．in hospital |
At the age of 60, his grandmother in a hospital for a long time every day.
| A．made fine toys | B．worked in the office |
| C．did the cleaning | D．stayed with his mother |
阅谴下面短文．筒要回答所给问题。
Welcome to Youth Radio, your radio. Here we're proud to introduce three Amazing Kids.
Gina, who is thirteen years old, got first prize in the "Young Cook of the Year" competition and she wants to write a recipe book for kids. "I want it to be fun to read and easy enough for children to use," she says. Gina learned by watching her father, who's also good at cooking, in the kitchen. She wants to encourage other children to cook because "everyone needs to eat so it's a skill that will always be useful!"
Seventeen-year-old Brian used to love running until he was hurt in a serious accident three years ago. He lost part of one leg and didn't even expect to walk again. Now he's an athlete who has recently taken part in a long race. "After my accident I wanted to give up," he says. "But now I'm happy to be alive and able to continue running."
Helen has always been good at science, but she thought it was too difficult to become an inventor. Then she heard about an accident that had happened when a car hit a train in her town. "That gave me an idea," says the clever sixteen-year-old. It took her over a year to invent a small special machine that tells car .drivers when a train is coming. One company is already interested in selling it, so it may be in he shops soon!
Do you know a child like them? Please e-mail us at amaxingkids@ mail. com and tell us why he or she should be on our radio. Thank you.What was Gina the winner of?
Does Gina want to write a children's recipe book? Why?
Why is it surprising that Brian is an athlete?
What is Helen's new invention used for?
What do you think the three Amazing Kids are like?
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