问题 选择题

下列离子方程式正确的是

A.氯化亚铁溶中通入氯气:Fe2++Cl2=Fe3++2Cl

B.硫酸铜溶液与氢氧化钡溶液反应:Ba2+ SO42―=BaSO4

C.氧化铜溶于硫酸: O2―+2H=H2O

D.碳酸钙溶于醋酸中:CaCO3+2CH3COOH=Ca2++2CH3COO+H2O+CO2

答案

答案:D

阅读理解

阅读理解。

     Scientists have argued for long over whether birds show real intelligence. Some scientists believe birds

have abilities(能力) including communication and different kinds of memory. In some unusual cases, their

abilities seem better than those of humans.

     Irene Pepperberg, a birds expert, did research about a grey parrot named. Griffin. Ms. Pepperberg says

Griffin can arrange objects in order of size. She says the talking bird also can combine words in the right

order. For example, he will combine words when asking for a piece of food. The researcher says experts

had thought that only humans and other mammals with large brains have the ability to combine objects and

words. She believes that bird brains have the ability to understand that complex(复杂的) tasks must be done

in the correct order.

     Some birds have other memory skills. For example, they collect and store thousands of seeds in autumn,

and find them later in winter. Alan Kamil and Alan Bond of the University of Nebraska are studying the

memories of birds called jays and nutcrackers. Their experiments show that these birds use natural objects to

find the seeds they have stored.

     It's said some birds can learn as many as 2,000 different songs. Songs may have developed as a way for

birds to communicate with other birds.

     According to Verner Bingman of Bowling Green State University in Ohio, birds must have a special

guidance system in their brain. He says that understanding how a bird's brain operates may help us better

understand how a human brain processes information.

     However, some scientists do still believe birds do many things that appear to be acts of thoughtful

intelligence. In most cases, they say, their behavior is simply instinctive (本能的), no reasoning power

directing it.

1. What is the main subject discussed in the passage?

A. The intelligence of birds.

B. Irene Pepperberg's study on birds.

C. The difference between humans and birds.

D. Ways for experts to train birds.

2. What's the main idea of Paragraphs 2-3?

A. Griffin, jays and nutcrackers are clever birds.

B. Objects help birds remember things.

C. Birds are as intelligent as humans.

D. Birds have certain memory skills.

3. It can be inferred from this passage that______.

A. most scientists believe birds have real intelligence

B. mammals understand the relationship between objects and words

C. maybe trees help jays to find the seeds they have stored

D. birds always communicate with one anther by singing

单项选择题