The "balance of nature" is not an empty phrase. Nature provides a population to occupy a suitable environment and cuts down surplus population to fit the available food supply. One means of reducing surplus population is predators(食肉动物); others are parasites (寄生虫) and diseases. Also, population density produces nervous disorders and even drives animals to mass migrations, like the lemmings (旅鼠) of Norway who plunge into (跳入) the sea.
That predators populations increase to control other animals has long been known. Many years ago, the Hudson’s Bay Company records revealed that the fox population went up and down about a year after the rabbit population had gone up and down.
Sometimes a situation occurs in which the predators population is reduced to a level below which nature can readily replace. On Valcour Island in Lake Champlain (New York) , a costly campaign resulted in the elimination of predatory animals only to have birds and small animals—including grouse (松鸡) and hares, popular game (猎物)—increase for four years afterward. Then lacking predator control, nature resorted to disease to cut down these populations.
Jamaica had an example of nature’s persistence in providing animals for existing habits. Sugar planters, about 75 years ago, imported mongooses to control rats. The mongooses killed off the rats and, with plentiful food, multiplied. Rats became scarce and the mongooses ate lambs, kids, puppies (小狗), and wildlife. Eventually, food became scarce and the mongoose’s population declined.

When the mongooses in Jamaica killed off the rats, they （　）

A:quickly died for lack of food B:attacked humans C:became problems themselves D:ate the sugar crop

Would you eat a bacon, lettuce and love apple sandwich You probably have eaten many of them. Love apple was the name used many years ago for the tomato.
The tomato is originally an American plant. It was found in South America by early Spanish explorers. The word tomato comes from the native Nahuatl word tomatl. But when it moved north, the plant earned a different name. Remarkably, the settlers in North America thought it was poisonous. They believed that to eat it was surely to die. It was said that deserted suitors would threaten to eat a tomato to cause their coldhearted lovers regret. Because of this legend, the settlers called the tomato a "love apple." While people enjoyed other native plants such as corn and sweet potatoes, everyone avoided the tomato.
No one knows who first dared to eat a tomato. Perhaps someone was brave enough, or lovesick enough, to try out the truth of the rumors. Of course, whoever ate this fruit was perfectly safe. No one died from eating a love apple. Still, it was many years before the people fully believed that the tomato was a safe, and even good food. But its use did become common, and the plant was sent across the ocean to become part of many traditional European dishes.

North American people didn’t eat tomatoes at first because （　）

A:they had too much other food B:they mistakenly thought they were poisonous C:settlers ate only traditional European foods D:no one liked the taste

Would you eat a bacon, lettuce and love apple sandwich You probably have eaten many of them. Love apple was the name used many years ago for the tomato.
The tomato is originally an American plant. It was found in South America by early Spanish explorers. The word tomato comes from the native Nahuatl word tomatl. But when it moved north, the plant earned a different name. Remarkably, the settlers in North America thought it was poisonous. They believed that to eat it was surely to die. It was said that deserted suitors would threaten to eat a tomato to cause their coldhearted lovers-regret. Because of this legend, the settlers called the tomato a "love apple." While people enjoyed other native plants such as corn and sweet potatoes, everyone avoided the tomato.
No one knows who first dared to eat a tomato. Perhaps someone was brave enough, or lovesick enough, to try out the truth of the rumors. Of course, whoever ate this fruit was perfectly safe. No one died from eating a love apple. Still, it was many years before the people fully believed that the tomato was a safe, and even good food. But its use did become common, and the plant was sent across the ocean to become part of many traditional European dishes.

North American people didn’t eat tomatoes at first because （）

A:they had too much other food B:they mistakenly thought they were poisonous C:settlers ate only traditional European foods D:no one liked the taste

Would you eat a bacon, lettuce and love apple sandwich You probably have eaten many of them. Love apple was the name used many years ago for the tomato.
The tomato is originally an American plant. It was found in South America by early Spanish explorers. The word tomato comes from the native Nahuatl word tomatl. But when it moved north, the plant earned a different name. Remarkably, the settlers in North America thought it was poisonous. They believed that to eat it was surely to die. It was said that deserted suitors would threaten to eat a tomato to cause their coldhearted lovers-regret. Because of this legend, the settlers called the tomato a "love apple." While people enjoyed other native plants such as corn and sweet potatoes, everyone avoided the tomato.
No one knows who first dared to eat a tomato. Perhaps someone was brave enough, or lovesick enough, to try out the truth of the rumors. Of course, whoever ate this fruit was perfectly safe. No one died from eating a love apple. Still, it was many years before the people fully believed that the tomato was a safe, and even good food. But its use did become common, and the plant was sent across the ocean to become part of many traditional European dishes.

North American people didn’t eat tomatoes at first because（　）

A:they had too much other food B:they mistakenly thought they were poisonous C:settlers ate only traditional European foods D:no one liked the taste

Would you eat a bacon, lettuce and love apple sandwich You probably have eaten many of them. Love apple was the name used many years ago for the tomato.
The tomato is originally an American plant. It was found in South America by early Spanish explorers. The word tomato comes from the native Nahuatl word tomatl. But when it moved north, the plant earned a different name. Remarkably, the settlers in North America thought it was poisonous. They believed that to eat it was surely to die. It was said that deserted suitors would threaten to eat a tomato to cause their coldhearted lovers regret. Because of this legend, the settlers called the tomato a "love apple." While people enjoyed other native plants such as corn and sweet potatoes, everyone avoided the tomato.
No one knows who first dared to eat a tomato. Perhaps someone was brave enough, or lovesick enough, to try out the truth of the rumors. Of course, whoever ate this fruit was perfectly safe. No one died from eating a love apple. Still, it was many years before the people fully believed that the tomato was a safe, and even good food. But its use did become common, and the plant was sent across the ocean to become part of many traditional European dishes.
North American people didn’t eat tomatoes at first because ______.

A:they had too much other food B:they mistakenly thought they were poisonous C:settlers ate only traditional European foods D:no one liked the taste

Before they ate the apple, Adam and Eve ______.

A:knew they were naked but didn' t feel ashamed B:knew nothing about shame and didn' t know they were naked C:covered their bodies with leaves and were not ashamed D:were not ashamed because they were not naked

Passage Five
When God made the first man, he put him in a beautiful garden, the Garden of Eden. Here Ad am lived in peace with all the animals. God gave Adam eternal life. But Adam was lonely in the gar den, so God made Eve. When Adam was asleep one night, God took a rib from him and made Eve, the first woman. Adam was happy when he woke up the next morning and found Eve beside him. God said to them, "Here in the Garden you have everything. But you cannot have one thing: you cannot eat the apples from the Tree of Knowledge."
One day Satan came to the Garden. He changed into a snake and went to live in the Tree of Knowledge. When Eve came near the tree one day, the snake called her. He gave her an apple and said," Take this apple and eat it. Don’ t listen to the God. Eat it. "After Eve took a bite, she the apple to Adam. He was afraid, but Eve repeated again and again: "It’ s good. Here, eat it. Why not" So he finally ate the apple.
Before they ate the apple; Adam and Eve didn’ t know that they were naked. But now they were ashamed and covered their bodies with leaves. God was angry with them. He said, "Leave the Gar den. You cannot stay here."
When Adam and Eve left the garden, they had their first experience of pain and hard work in the cold hard world outside.

Which of the following statements is not true（）

A:Satan tempted(旅惑) Eve to eat the apple first. B:Eve persuaded Adam to eat the apple after her. C:Adam also ate the apple without hesitating. D:Both Adam and Eve finally forgot God' s words.

Passage Five When God made the first man, he put him in a beautiful garden, the Garden of Eden. Here Ad am lived in peace with all the animals. God gave Adam eternal life. But Adam was lonely in the gar den, so God made Eve. When Adam was asleep one night, God took a rib from him and made Eve, the first woman. Adam was happy when he woke up the next morning and found Eve beside him. God said to them, "Here in the Garden you have everything. But you cannot have one thing: you cannot eat the apples from the Tree of Knowledge." One day Satan came to the Garden. He changed into a snake and went to live in the Tree of Knowledge. When Eve came near the tree one day, the snake called her. He gave her an apple and said," Take this apple and eat it. Don’ t listen to the God. Eat it. "After Eve took a bite, she the apple to Adam. He was afraid, but Eve repeated again and again: "It’ s good. Here, eat it. Why not" So he finally ate the apple. Before they ate the apple; Adam and Eve didn’ t know that they were naked. But now they were ashamed and covered their bodies with leaves. God was angry with them. He said, "Leave the Gar den. You cannot stay here." When Adam and Eve left the garden, they had their first experience of pain and hard work in the cold hard world outside.

Which of the following statements is not true（）

A:Satan tempted(旅惑) Eve to eat the apple first. B:Eve persuaded Adam to eat the apple after her. C:Adam also ate the apple without hesitating. D:Both Adam and Eve finally forgot God' s words.

Passage Two

North American people didn’t eat tomatoes at first because ______.

A:they had too much other food B:they mistakenly thought they were poisonous C:settlers ate only traditional European foods D:no one liked the taste