题目内容
5. Who do you think is to blame for the (失败) of the plan?
5. failure
3. we shall start.(强调until引导的时间状语)
在你回来之前，我们不会开始的。
Plants have family values,too,it seems,with new research sug?gesting they can recognize close relatives in order to work together.
An ability to tell family from strangers is well known in animals,allowing them to cooperate and share resources,but plants may pos?sess similar social skills,scientists believe.
Susan Dudley and Amanda File of McMaster University in Ontario? Canada,report they have demonstrated for the first time that plants can recognize their kin.
This suggests that plants,though lacking recognition and memory,are capable of complex social interactions.
"Plants have this kind of hidden but complicated social life," Dudley said.
The study found plants from the same species of beachdwelling wild flower grew aggressively alongside unrelated neighbours but were less competitive when they shared soil with their families.
Sea rocket,a North American species,showed stronger and healthier root growth when planted in pots with strangers than when raised with relatives from the same ma?ternal (母系的) family,the study found.
This is an example of kin selection,a behaviour common in animals in which closely related individuals take a group approach to succeeding in their environment,the researchers said.
Kin selection also applies to competition,because if family members compete less with each other,the group will do better overall. "Everywhere you look,plants are growing right up next to other plants," Dudley said. "Usually it's a case of each plant for itself. But sometimes those plants are related,and there are bene?fits to not wasting resources on being competitive,and there is not really a cost to not being competitive as long as your neighbour is also not being competitive."
Learning and memory appear to be important for kin recognition in animals,but this isn't an option for plants,she noted.
Some researchers speculate (猜测) that plants communicate through their roots,identifying themselves using tiny chemical signatures specific to each plant's family.
5. What's the main idea of the passage?
A. Studies find plants can recognize and communicate with relatives.
B. Kin selection is important for plants.
C. Animals can recognize and memorize their relatives.
D. Competition asks plants to recognize their relatives.
6. Which of the following is NOT right about animals' social skills?
A. Animals can recognize and memorize their relatives.
B. Animals' social skills are to cooperate and share resources.
C. Animals' social skills can recognize close relatives to work together.
D. Animals' social skills are no use at all.
7. Plants' kin selection is to .
A. grow well
B. compete with other kinds of plants
C. strengthen the relationship among siblings
D. find which one is the best
8. From the passage,we learn that .
A. sea rocket is a South American species
B. sea rocket grows aggressively alongside unrelated neighbours
C. sea rocket grows aggressively alongside its siblings
D. sea rocket is a kind of bush without flowers
2. More and more people (沉迷于玩) their cellphones even in front of their family and their friends.
10. How many times do you dine out per week (平均) ?
2. average,there are 200 visitors to the exhibition every day.
1. 有时我想知道我们是否能到达那里。
There were times when I wondered we would get there.(whether…or…)
3. The parents felt helpless when they found their son had been addicted
computer games for long.
2. It was that he said at the meeting that disappointed me.
