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2921．You
（want）on the telephone now.发布：2024/5/23 20:38:36组卷：0引用：1难度：0.72922．Perhaps the day will come
people will be able to travel in space frequently.发布：2024/5/23 20:38:36组卷：0引用：1难度：0.72923．-Did Peter fix the computer himself？
-He had it（fix），because he doesn't know much about computers.发布：2024/5/23 20:38:36组卷：0引用：1难度：0.62924．The plan has been set up to help
people.（home）发布：2024/5/23 20:38:36组卷：1引用：0难度：0.72925．The patient
on by the doctors right now.
医生们正在给这个病人做手术。发布：2024/5/23 20:38:36组卷：2引用：1难度：0.7
2926．Plants cannot run or hide，so they need other strategies to avoid being eaten．Some curl up their leaves；others produce chemicals to make themselves taste bad if they sense animals drooling on them，chewing them up or laying eggs on them-all signals of an attack．New research now shows some flora can feel a plant-eating animal well before it launches an attack，letting a plant prepare a preemptive（抢先的）defense that even works against other pest species．
When ecologist John Orroek of the University of Wisconsin-Madison sprayed snail slime-a liquid the animals release as they slide along-into soil，nearby tomato plants appeared to notice．They．increased their levels of an enzyme（生化酶），which is known to prevent plant-eating animals．"None of the plants were ever actually attacked．"Orrock says．"We just gave them cues that suggested an attack was coming，and that was enough to cause big changes in their chemistry．"
Initially Orrock found this defense worked against snails；in the latest study，his team measured the slimy warning impact on another potential threat．The investigators found that hungry-caterpillars（毛虫），which usually eat tomato leaves greedily，had no appetite for them after the plants were exposed to snail slime and activated their chemical resistance．This nonspecifie defense may be a strategy that benefits the plants by further improving their overall possibilities of survival，says Orrock，who reported the results with his colleagues in March in Oecologia．
The finding that a snail's approach can cause a plant response that afiects a different animal made Richard Karban curious，a plant communications expert，who was not involved in the study．"It is significant that the plants are responding before being damaged and that these cues are having such far-ranging effects，" Karban says．The research was comprehensive，he adds，but he wondern how the tomato plants felt chemicals in snail slirae that never actually touched them．
"That's the million-dollar question，"Orrock says．He hopes ruture research will make out the mechanisms that enable plants to sense these relatively distant cues．
（1）What can be a suitable title for the text？
A．Watchful Plants
B．Greedy Animals
C．A Snail's Approach
D．A Defense Attack
（2）John Orrock sprayed a liquid into soil nearby tomato plants to．
A．make them grow better
B．give tomato plants a warning
C．keep plant-eating animals away
D．inform plant-eating animals of danger
（3）Why is the example of"caterpillars"mentioned in Paragraph 3？
A．To introduce another animal．
B．To confirm the result of the study．
C．To appeal to people to protect animals．
D．To analyse different resistance chemicals．
（4）What does Richard Karban really want to know？
A．How tomato plants become aware of danger．
B．What the chemicals in the snail slime are．
C．Whether the research is of practical value．
D．What the finding of the research is．发布：2024/5/23 20:38:36组卷：10引用：1难度：0.52927．The 80，000 objects
（collect） by Sir Hans Sloane，for example，formed the core collection of the British Museum which opened in 1759.发布：2024/5/23 20:38:36组卷：13引用：2难度：0.92928．被老师的话鼓舞后，他学习更刻苦了。
发布：2024/5/23 20:38:36组卷：2引用：0难度：0.82929．
you have made a promise，you must carry it out.发布：2024/5/23 20:38:36组卷：1引用：2难度：0.72930．Ham，sausage and other
（process） meats can lead to cancer，according to a report.发布：2024/5/23 20:38:36组卷：1引用：1难度：0.7
