What are fossils?

Fossils are the remains of plants or animals. For such remains to be considered fossils, scientists have decided they have to be over 10,000 years old. The word fossil comes from the Latin word “fossilis”, which means, “dig up”.  Fossils can be divided into “body fossils” and “trace(痕迹) fossils”. Body fossils are the remains of a plant or animal’s body. Trace fossils are the remains of the activity of an animal, such as footprints, egg shells, and nests.

How are fossils formed?

Some animals were quickly covered after their death by sediment(沉淀物) like earth, mud or sand. Over time, the parts of the animals that didn’t rot (usually the harder parts like bones and teeth) were covered in the newly formed sediment. Then, a lot of chemical changes happened to the animals bodies. Water with minerals(矿物质) went into the bone and took the place of the chemicals in the bone with rock-like minerals. In the end we get a heavy, rock-like copy of the original object - a fossil. There weren’t any changes in size and shape when an object changed into a fossil, but the fossil of a bone doesn’t have any bone in it! It is chemically more like a rock! According to scientists, fossils have been found on every continent(大陆) on Earth.

1.Trace fossils can’t be formed from the ______ of some kind of animals.

A. footprints B. nests C. eggs D. bodies

2.______ brings the rock-like minerals into the bone.

A. Sunlight B. Earth C. Water D. Air

3.According to the last paragraph, the fossil is as ______ as the original object.

A. heavy B. big C. old D. clean

4.We can know that ______ from the passage.

A. scientists think that the fossils may have a history of 100 centuries.

B. people haven’t found any fossil on the continent of Africa.

C. we can find some real bones in the fossils of a bone.

D. there are many kinds of sediment in the fossils.

5.This passage most probably comes from ______.

A. an advertisement B. a medical magazine C. a science book D. a notice

Mobile phones(手机) have become a problem for middle schools. Some middle schools in Australia have stopped students from carrying mobile phones during school hours. The mobile phone use among children has become a problem for the school this year. Several children have got mobile phones as Christmas gifts, and more students will want them.

Mary, a teacher, said the mobile phone use is a distraction to students during school hours and it also gives teachers so much trouble in their classrooms. Teachers also said that sometimes students might use phone messages to copy during exams. She said some schools tried to stop mobile phones. Some parents felt unhappy because they couldn’t get in touch with their children.

Many teachers said students should not have mobile phones at school, but if there was a good reason, they could leave their phones at the school office. They also said there were many reasons why the students should not have mobile phones at school, they were easy to lose and were a distraction for studies.

Many people say that they understand why parents would want their children to have phones, but they think schools should let the students know when they can use their mobile phones.

1.Some middle schools in Australia have stopped students from carrying mobile phones .

A. because they are students B. when they are free

C. when they are at school D. because they are children

2.We know from the passage that some children get mobile phones from____

A. the makers and sellers B. the teachers

C. their parents and friends D.some mobile phone users

3.What does the underlined word mean in the passage?

A. 鼓舞 B. 分心 C. 奖励 D. 核对

4.Some parents felt unhappy because they couldn’t _ __ during school hours.

A. use their mobile phones

B. leave their mobile phones at the school office

C. help the teachers with their work

D. get in touch with their children

5.The passage mainly tells us that _ __.

A. students shouldn’t have mobile phones at school except(除…外) some special reasons

B. it is impossible to stop students from using mobile phones at school

C. some parents felt unhappy because they couldn’t use their phones at school

D. parents should teach children how to use mobile phones during school hours

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