[单项选择]Researchers have discovered a new poison, bromethalin, that is lethal to all rats, even to those species that have become immune to other poisons, as well as to those rats that eat only the most minute quantities. Tests have demonstrated that rats will not learn to avoid bromethalin and that carcasses of rats killed by bromethalin pose no threat to the well-being of other animals.
Which of the following statements, if true, would support the researchers’ claim that carcasses of rats killed by bromethalin will not pose a threat to other animals
A. Rats that consume bromethalin die immediately.
B. Animals, prompted by curiosity, often examine carcasses that appear in their territory.
C. Chemicals in the digestive tract of dead rats quickly break bromethalin down into a nontoxic substance.
D. Traces of bromethalin remain in the rat’s mouth and saliva after the rat eats the poison.
E. (E) Certain animals are scavengers and feed habitually on refuse and dead flesh.

[单项选择]Researchers discovered that plants infected with a virus give off a gas that（）disease resistance in neighboring plants.
A. contracts
B. activates
C. maintains
D. prescribe

[填空题]Some researchers have discovered that chimpanzees have a hallmark of human culture.

[单项选择]Researchers have discovered that ______ with animals in an active way may lower a person’s blood pressure.
A. merging
B. migrating
C. interacting
D. integrating

[填空题]The (poison) （） gases from the cars have polluted the air.

[填空题]The(poison)（）gases from the cars have polluted the air.

[单项选择]Physicists have made new discoveries that challenge our（）theories of the universe.
A. existed
B. adapted
C. accepted
D. established

[填空题]The (poison) ______ gases from the cars have polluted the air.

[填空题]Schools looking to ban cell phones may have a new excuse: a growing number of people are developing an allergy (过敏) to metal in the devices. We all know that food allergies are on the rise—a study last year placed the rate at 1 per 70 children, compared with 1 in 250 in the 1970s. But at last month’s meeting of the American College of Allergy, Asthma & Immunology, allergists reported that many substances that once seemed harmless are now leading to allergic reactions too.
Allergies can develop when young bodies come into contact with a new substance, and an increasing number of kids have early exposure to tech tools and "adult" products that can lead to a lifetime of reactions. For instance, the nickel hardware often used on phone trim and faceplates can lead to red, itchy (发痒的) skin where the phone is pressed against the face of someone who developed a nickel allergy at a young age. It’s especially problematic for women, says Luz Fonacier, an allergist who presented at the conf

[单项选择]We have a new student in our class. Her name is Ann. She is an American girl. She is twelve. Jeremy is her brother. He is fourteen. He is a student in Grade Three in our school. Their father is our English teacher, Their mother is an English teacher in our school, too.
Ann and Jeremy are in the same school.
[A] True
[B] False