问题 选择题

自然界中存在很多像14C的放射性原子,这些天然放射现象的发现说明(  )

A.原子不可以再分

B.原子的核式结构

C.原子核还可以再分

D.原子核是由质子和中子构成

答案

天然放射现象中,原子核发生衰变,生成新核,同时有中子产生,因此说明了原子核可以再分,

故选C.

阅读理解

Su Hua is studying at Cambridge, UK. She has bought a bicycle and is worried about security. Her friend, Kate, found this article and sent it to her.

Introduction

A lot of crime is against bicycles. About 150,000 bicycles are stolen every year and most are never found. You can prevent this happening by following a few careful steps.

Basic Security

Do not leave your bicycle in out-of-the-way places. Always lock your bicycle when you leave. Secure it to lampposts or trees. Take off smaller parts and take them with you, for example lights and saddles(车座).

Locks

Get a good lock. There are many different types in the shop. Buy one that has been tested against attack. Ask for a recommendation from a bike shop.

Marking

Security marking your bike can act as a deterrent(威慑) to a thief. It can also help the police find your bicycle. It should be clearly written and include your postcode and your house or flat number. This will provide a simple way to identify your bicycle.

Registration

There are a number of companies who will mark your bicycle for you. They will then put your registration number and personal details on their computer database. Then if your bicycle is found it will be easy to contact you.

Finally

Keep a record of the bicycle yourself: its make, model and registration number. You can even take a photograph of it, this will prove the bicycle belongs to you.

小题1:Which part of the article gives you information on how to lock up your bicycle when you leave it?

A.Locks

B.Marking

C.Registration

D.Basic Security小题2:The article advises you to keep a record of your bicycle ____________.

A.in the bike shop and your computer

B.in a police station and security company

C.in a security company and your university

D.by yourself and in a security company小题3:Which of the following statements is true?

A.More than 150,000 bicycles are stolen every year.

B.Leave your bicycle in out-of-the-way places.

C.Taking a photograph of your bike will help prove the bicycle belongs to you.

D.Always lock your bicycle even if you don’t leave.小题4:The main purpose of this article is _____________.

A.to tell you what to do if your bicycle is stolen

B.to suggest ways of keeping your bicycle safe

C.to give you advice on where to buy a good lock

D.to say why you shouldn’t keep your bicycle in a quiet place

问答题 简答题