Not all memories are sweet. Some people spend all their lives trying to forget bad experiences .Violence and traffic accidents can leave people with terrible physical and emotional scars . Often they relive (重新体验) these experiences in nightmares .

Now American researchers think they are close to developing a pill ,which will help people forget bad memories . The pill is designed to be taken immediately after a frightening experience . They hope it might reduce , or possible erase (抹去) the effect of painful memories .

In November, experts tested a drug on people in the US and France. The drug stops the body releasing chemicals that fix memories in the brain . So far the research has suggested that only the emotional effects of memories may be reduced , not that the memories are eased .

The research has caused a great deal of argument . Some think it is a bad idea , while others support it . Supporters say it could lead to pills that prevent or treat soldiers’ troubling memories after war .

They say that there are many people who suffer from terrible memories . “Some memories can ruin people’s lives . They come back to you when you don’t want to have them in a daydream or nightmare . They usually come with very painful emotions ,” said Roger Pitman , a professor of psychiatry (精神病学) at Harvard Medical School. “This could relieve a lot of that suffering .”

But those who are against the research say that changing memories is very dangerous because memories give us our identity (物质). They also help us all avoid the mistakes of the past . “All of us can think of bad events in our lives that were horrible at the time but make us who we are . I’m not sure we’d want to wipe those memories out.” said Rebecca Dresser , a medical ethicist (伦理学家).

Some people fear that although the drug would first be used in only very serious cases , it would become more and more common . “People always have the ability to misuse science,” said Joeph Le Doux, a New York University memory researcher . “All we want to do is help people have better control of memories .”

What’s the main idea of the text ?

      A．People often suffer from bad memories .

       B．American researchers are trying to develop a pill .

       C．Forget bad memories , and be happy .

       D．The research has cause a heated argument .

The underlined word “it” in paragraph 4 refers to “       ”.

       A．the new drug          B．the research into the drug

       C．the memory            D．the chemical in the drug  

Which of the following is not the opinion of the supporters ?

       A．The pill can erase all the memories in the past

       B．Some memories can ruin people’s lives. The pill can relieve emotional suffering .

       C．The pill can also help many other types of people who suffer from terrible memories .

       D．The pill can also prevent or treat troubling memories in soldiers after war

Which of the following is not the opinion of the opponents (反对者)?

       A．Our memories give us our identity .

       B．The memories help humanity avoid mistake of the past .

       C．The drug should be used in only very serious cases .

       D．People may not be sure whether they want to wipe the memories out .

It could be inferred from the passage that         .

       A．the pill has been developed and will be more and more common

       B．the pill has helped soldiers forget bad experiences during the war .

       C．The pill is being tested on some people by some researchers .

       D．The pill will be forbidden because people have different opinions of it .

Not all memories are sweet. Some people spend all their lives trying to forget bad experiences. Violence and traffic accidents can leave people with terrible physical and emotional scars. Often they relive （重新体验） these experiences in nightmares.

Now American researchers think they are close to developing a pill, which will help people forget bad memories. The pill is designed to be taken immediately after a frightening experience. They hope it might reduce, or possibly erase （抹去）, the effect of painful memories.

In November, experts tested a drug on people in the US and France. The drug stops the body releasing chemicals that fix memories in the brain. So far the research has suggested that only the emotional effects of memories may be reduced, not that the memories are erasea.

The research has caused a great deal of argument. Some think it is a bad idea, while others support it. Supporters say it could lead to pills that prevent or treat soldiers' troubling memories after war.

They say that there are many people who suffer from terrible memories. "Some memories can ruin people's lives. They come back to you when you don't want to have them in a daydream or nightmare. They usually come with very painful emotions," said Roger Pitman, a professor of psychiatry （精神病学） at Harvard Medical School. "This could relieve a lot of that suffering."

But those who are against the research say that changing memories is very dangerous because memories give us our identity （特质）. They also help us all avoid the mistakes of the past. "All of us can think of bad events in our lives that were horrible at the time but make us who we are. I'm not sure we'd want to wipe those memories out," said Rebecca Dresser, a medical ethicist （伦理学家）.

Some people fear that although the drug would first be used in only very serious cases, it would become more and more common. "People always have the ability to misuse science," said Joseph LeDoux, a New York University memory researcher. "All we want to do is help people have better control of memories."

1．What’s the main idea of the text?

A．People often suffer from bad memories.

B．American researchers are trying to develop a pill.

C．Forget bad memories, and be happy.

D．The research has caused a heated argument.

2．The underlined word “it” in paragraph 4 refers to “_____”.

A．the new drug                         B．the research into the drug

C．the memory                               D．the chemical in the drug

3．Which of the following is not the opinion of the supporters?

A．The pill can erase all the memories in the past.

B．Some memories can ruin people’s life. The pill can relieve emotional suffering.

C．The pill can also help many other types of people who suffer from terrible memories.

D．The pill can prevent or treat troubling memories in soldiers after war.

4．Which of the following is not the opinion of the opponents （反对者）?

A．Our memories give us our identity.

B．The memories help humanity avoid mistakes of the past.

C．The drug should be used in only very serious cases.

D．People may not be sure whether they want to wipe the memories out.