问题 单项选择题

下列关于类和对象的叙述中,错误的是

A.一个类只能有一个对象

B.对象是类的具体实例

C.类是对某一类对象的抽象

D.类和对象的关系是一种数据类型与变量的关系

答案

参考答案:A

解析: 本题考核类和对象的概念.类是用户定义的一种类型,程序员可以使用这个类型来说明多个变量,即对象。

阅读理解

阅读理解。

    

     Jogging is basically running at a steady (稳定的) speed over short or long distances. It became popular

some twenty years ago and has remained a favorite way of keeping fit for lots of people.

     One of the main advantages of jogging over many other sports is that it can be done anywhere. People jog

in parks, in the country side and even in urban areas. No special equipment is required no costly hats, or balls,

and no expensive sports kit. Good quality running shoes are advisable. Special jogging suits are widely available

these days and can be bought quite cheaply but are not necessary. In addition to being able to jog anywhere,

you can also jog at any time, in any season! It's not unusual to see joggers exercising in the height of summer

or in the depth of winter!

     The act of jogging doesn't require any special training or skill. You do need to be basically healthy and then,

after a few basic warm-up bends and stretches, you are ready to begin. You simply start running, gently, and

then build up to a steady speed. Do not overtire yourself by trying to go too fast. It is best for you to run at

a steady and comfortable speed.

     Jogging is a single sport. You don't need to wait until you have gathered a team or found a partner. You

can jog alone. A few words of warning however: lone women joggers should be especially careful when

choosing jogging routes, particularly at night time.

     Jogging is excellent for keeping fit. It's good for the lungs, the heart and the circulation. It's easy and

it's convenient. Why don't you try it? If you require more information, talk to one of the instructors at the

sports centre. We are only too happy to help. Please remember: if you do decide to jog, talk to your doctor

first if you have any health worries. Happy jogging!

1. Is jogging a good way of keeping fit?

    _____________________________________

2. Which are more necessary for joggers, good quality running shoes or special jogging suits? 

    _____________________________________

3. What is hest for us to jog? 

    _____________________________________

4. What's the writer's special suggestion to lone women who decide to jog? 

    _____________________________________

5. What does the writer want to tell us in the passage? 

    _____________________________________

单项选择题