词汇：

dioxide [daɪˈɒksaɪd] n. 二氧化物

lava ["lɑ:və] n. 熔岩

Permian [ˈpə:miən] adj. 二叠纪

gigaton ["dʒɪgətʌn] n. 十亿吨梯恩梯

genera ["dʒenərə] n. 种类

dinosaurs ["daɪnəsɔ:z] n. 恐龙

asteroid [ˈæstərɔɪd] n. 小行星

注释：

1.The Permian extinction:二叠纪物种灭绝

Why did older volcanic eruptions do more damage than more recent ones？

A:Because they killed off life more easily. B:Because they were brighter. C:Because they were larger. D:Because they were hotter.

Text 4
The age at which young children begin to make moral discriminations about harmful actions committed against themselves or others has been the focus of recent research into the moral development of children. Until recently, child psychologists supported pioneer developmentalist Jean Piaget in his hypothesis that because of their immaturity, children under age seven do not take into account the intentions of a person committing accidental or deliberate harm, but rather simply assign punishment for offences on the basis of the magnitude of the negative consequences cause.
According to Piaget, children under age seven occupy the first stage of moral development, which is characterized by moral absolutism (rules made by authorities must be obeyed) and imminent justice (if rules are broken, punishment will be meted out). Until young children mature, their moral judgments are based entirely on the effect rather than the cause of an offence. However, in recent research, Keasey found that six-year-old children not only distinguish between accidental and intentional harm, but also judge intentional harm as naughtier, regardless of the amount of damage produced. Both of these findings seem to indicate that children, at an earlier age than Piaget claimed, advance into the second stage of moral development, moral autonomy, in which they accept social rules but view them as more arbitrary than do children in the first stage.
Kensey’s research raises two key questions for developmental psychologists about children under age seven: do they recognize justifications for harmful actions, and do they make distinctions between harmful acts that are preventable and those acts that have unforeseen harmful consequences.’ Studies indicate that justifications excusing harmful actions might include public duty, self-defense, and provocation. For example, Nesdale and Rule concluded that children were capable of considering whether or not an aggressor’s actions was justified by public duty: five year olds reacted very differently to "Bonnie wrecks Ann’s pretend house" depending on whether Bonnie did it "so somebody won’t fall over it" or because Bonnie wanted "to make Anne feel bad." Thus, a child of five begins to understand that certain harmful actions, though intentional, can be justified: the constraints of moral absolutism no longer solely guide their judgements.
Psychologists have determined that during kindergarten children learn to make subtle distinctions involving harm. Darley observed that among acts involving unintentional harm, six-year-old children just entering kindergarten could not differentiate between foreseeable, and thus preventable, harm and unforeseeable harm for which the offender cannot be blamed. Seven months later, however, Darley found that these same children could make both distinctions, thus demonstrating that they had become morally autonomous.

A:the punishment is to be administered immediately following the offence. B:the more immature a child, the more severe the punishment assigned. C:the punishment for acts of intentional harm is less severe than it is for acts involving acci- dental harm. D:the severity of the assigned punishment is primarily determined by the perceived magnitude of negative consequences.

Text 4 The age at which young children begin to make moral discriminations about harmful actions committed against themselves or others has been the focus of recent research into the moral development of children. Until recently, child psychologists supported pioneer developmentalist Jean Piaget in his hypothesis that because of their immaturity, children under age seven do not take into account the intentions of a person committing accidental or deliberate harm, but rather simply assign punishment for offences on the basis of the magnitude of the negative consequences cause. According to Piaget, children under age seven occupy the first stage of moral development, which is characterized by moral absolutism (rules made by authorities must be obeyed) and imminent justice (if rules are broken, punishment will be meted out). Until young children mature, their moral judgments are based entirely on the effect rather than the cause of an offence. However, in recent research, Keasey found that six-year-old children not only distinguish between accidental and intentional harm, but also judge intentional harm as naughtier, regardless of the amount of damage produced. Both of these findings seem to indicate that children, at an earlier age than Piaget claimed, advance into the second stage of moral development, moral autonomy, in which they accept social rules but view them as more arbitrary than do children in the first stage. Kensey’s research raises two key questions for developmental psychologists about children under age seven: do they recognize justifications for harmful actions, and do they make distinctions between harmful acts that are preventable and those acts that have unforeseen harmful consequences.’ Studies indicate that justifications excusing harmful actions might include public duty, self-defense, and provocation. For example, Nesdale and Rule concluded that children were capable of considering whether or not an aggressor’s actions was justified by public duty: five year olds reacted very differently to "Bonnie wrecks Ann’s pretend house" depending on whether Bonnie did it "so somebody won’t fall over it" or because Bonnie wanted "to make Anne feel bad." Thus, a child of five begins to understand that certain harmful actions, though intentional, can be justified: the constraints of moral absolutism no longer solely guide their judgements. Psychologists have determined that during kindergarten children learn to make subtle distinctions involving harm. Darley observed that among acts involving unintentional harm, six-year-old children just entering kindergarten could not differentiate between foreseeable, and thus preventable, harm and unforeseeable harm for which the offender cannot be blamed. Seven months later, however, Darley found that these same children could make both distinctions, thus demonstrating that they had become morally autonomous.

A:the punishment is to be administered immediately following the offence. B:the more immature a child, the more severe the punishment assigned. C:the punishment for acts of intentional harm is less severe than it is for acts involving acci- dental harm. D:the severity of the assigned punishment is primarily determined by the perceived magnitude of negative consequences.

Modern Drugs Doctors, sixty years ago, could do little to help victims of polio. Serious cases usually ended in death. In 1955, a vaccine was developed that prevented the disease. Today, polio is no longer a major health problem. Many of the most important drugs that doctors prescribe today have been developed in the last 30 years. Modern drugs are complex, specific and powerful. People need to know more about drugs in order to use them safely. Early people discovered by accident that some of the plants growing around them seemed useful to heal sores, relieve pain, or even cure diseases. These plants were the first drugs. Now plants are still the source of some drugs. Quinine, for example, is a bitter-tasting drug used to treat the chills and fever of malaria and to reduce attacks of the disease. It is made from the bark of the cinchona tree, which grows in the Andes Mountains. The Indians of that region were the first to use the bark as a medicine. The Spanish people probably brought it to Europe in the early 1600s. Chemists learned how to get the pure drug from the bark and in 1944; it was made artificially in the laboratory. Other important drugs, such as hormones and vaccines, are obtained from animals. But most of the modern drugs come from chemical combinations worked out by research scientists. Most people never see drugs in their simple form as chemicals. Instead, they are seen as tablets, capsules or liquids that contain the drug and other ingredients. People use drugs to get different results. Some drugs attack the organism that causes a disease. They cure by killing the organism. Other drugs relieve what we call the symptoms of the disease: the headache, pain, fever or chills, and make the patient more comfortable. These constitute most over-the-counter drugs. People can get them in drug stores. It seems to the author that the medicine used by early people______.

A:was of no real value B:was probably effective C:was easy to make D:did more harm than good

Modern Drugs Doctors, sixty years ago, could do little to help victims of polio. Serious cases usually ended in death. In 1955, a vaccine was developed that prevented the disease. Today, polio is no longer a major health problem. Many of the most important drugs that doctors prescribe today have been developed in the last 30 years. Modern drugs are complex, specific and powerful. People need to know more about drugs in order to use them safely. Early people discovered by accident that some of the plants growing around them seemed useful to heal sores, relieve pain, or even cure diseases. These plants were the first drugs. Now plants are still the source of some drugs. Quinine, for example, is a bitter-tasting drug used to treat the chills and fever of malaria and to reduce attacks of the disease. It is made from the bark of the cinchona tree, which grows in the Andes Mountains. The Indians of that region were the first to use the bark as a medicine. The Spanish people probably brought it to Europe in the early 1600s. Chemists learned how to get the pure drug from the bark and in 1944; it was made artificially in the laboratory. Other important drugs, such as hormones and vaccines, are obtained from animals. But most of the modern drugs come from chemical combinations worked out by research scientists. Most people never see drugs in their simple form as chemicals. Instead, they are seen as tablets, capsules or liquids that contain the drug and other ingredients. People use drugs to get different results. Some drugs attack the organism that causes a disease. They cure by killing the organism. Other drugs relieve what we call the symptoms of the disease: the headache, pain, fever or chills, and make the patient more comfortable. These constitute most over-the-counter drugs. People can get them in drug stores. It seems to the author that the medicine used by early people______.

A:was of no real value B:was probably effective C:was easy to make D:did more harm than good

Modern Drugs Doctors, sixty years ago, could do little to help victims of polio. Serious cases usually ended in death. In 1955, a vaccine was developed that prevented the disease. Today, polio is no longer a major health problem. Many of the most important drugs that doctors prescribe today have been developed in the last 30 years. Modern drugs are complex, specific and powerful. People need to know more about drugs in order to use them safely. Early people discovered by accident that some of the plants growing around them seemed useful to heal sores, relieve pain, or even cure diseases. These plants were the first drugs. Now plants are still the source of some drugs. Quinine, for example, is a bitter-tasting drug used to treat the chills and fever of malaria and to reduce attacks of the disease. It is made from the bark of the cinchona tree, which grows in the Andes Mountains. The Indians of that region were the first to use the bark as a medicine. The Spanish people probably brought it to Europe in the early 1600s. Chemists learned how to get the pure drug from the bark and in 1944; it was made artificially in the laboratory. Other important drugs, such as hormones and vaccines, are obtained from animals. But most of the modern drugs come from chemical combinations worked out by research scientists. Most people never see drugs in their simple form as chemicals. Instead, they are seen as tablets, capsules or liquids that contain the drug and other ingredients. People use drugs to get different results. Some drugs attack the organism that causes a disease. They cure by killing the organism. Other drugs relieve what we call the symptoms of the disease: the headache, pain, fever or chills, and make the patient more comfortable. These constitute most over-the-counter drugs. People can get them in drug stores. It seems to the author that the medicine used by early people______.

A:was of no real value B:was probably effective C:was easy to make D:did more harm than good

Modern Drugs Doctors, sixty years ago, could do little to help victims of polio. Serious cases usually ended in death. In 1955, a vaccine was developed that prevented the disease. Today, polio is no longer a major health problem. Many of the most important drugs that doctors prescribe today have been developed in the last 30 years. Modern drugs are complex, specific and powerful. People need to know more about drugs in order to use them safely. Early people discovered by accident that some of the plants growing around them seemed useful to heal sores, relieve pain, or even cure diseases. These plants were the first drugs. Now plants are still the source of some drugs. Quinine, for example, is a bitter-tasting drug used to treat the chills and fever of malaria and to reduce attacks of the disease. It is made from the bark of the cinchona tree, which grows in the Andes Mountains. The Indians of that region were the first to use the bark as a medicine. The Spanish people probably brought it to Europe in the early 1600s. Chemists learned how to get the pure drug from the bark and in 1944; it was made artificially in the laboratory. Other important drugs, such as hormones and vaccines, are obtained from animals. But most of the modern drugs come from chemical combinations worked out by research scientists. Most people never see drugs in their simple form as chemicals. Instead, they are seen as tablets, capsules or liquids that contain the drug and other ingredients. People use drugs to get different results. Some drugs attack the organism that causes a disease. They cure by killing the organism. Other drugs relieve what we call the symptoms of the disease: the headache, pain, fever or chills, and make the patient more comfortable. These constitute most over-the-counter drugs. People can get them in drug stores. It seems to the author that the medicine used by early people______.

A:was of no real value B:was probably effective C:was easy to make D:did more harm than good