问题 单项选择题

通过调查得知,并非所有个体商贩都有偷税、逃税行为。
如果上述调查的结论是真实的,则以下哪项一定为真

A.所有的个体商贩都没有偷税、逃税行为。

B.多数个体商贩都有偷税、逃税行为。

C.并非有的个体商贩没有偷税、逃税行为。

D.并非有的个体商贩有偷税、逃税行为。

E.有的个体商贩确实没有偷税、逃税行为。

答案

参考答案:E

解析: 题干的意思是所有的个体商贩都有偷税、逃税行为是假命题,而不是说所有的个体商贩都没有偷税、逃税行为。E肯定了有的个体商贩没有偷税、逃税行为,与题干相符,一定为真。

阅读理解

Always forgetting your long passwords(密码)? Worried about being hacked(被攻击)?All these worries will soon become history. Scientists have found that upper-casing(大写)your password can help you reduce the chance being hacked.

Usually passwords are six letters or more.However,50 percent of people choose a common word or simple key combination for their password. The most used passwords are 123456, abcdef and abc123. In fact, if your passwords are in lower-case(小写),it will be easily hacked by a hacker. According to a study, it only takes a hacker ten minutes to hack a six-letter password which is in lower-case, but if you make the letter in upper-case, it can take up to ten hours. So if you want to make your account much safer, you should make your password upper-case. Of course, you can also add numbers or symbols to your password. Most of the time a hacker’s computer has to work for 18 days to break a password, but if you choose a nine-letter password that includes numbers and symbols, it can take a hacher’s  computer 44,530 years to break it.

小题1:Scientists have found that   your password is much safer for  

your account.

A.upper-casing

B.lower-casing

C.reducing

D.copying小题2:According to the passage,______is not one of the most used

passwords.

A.123456

B.abcdef

C.abc123

D.000000小题3:It takes a hacker___to hack a six-letter password which is in

lower—case.

A.10 minutes

B.10 hours

C.18 days

D.44,530 years小题4:The Chinese meaning of the underlined word is       

A.数字     B.符号      C.色彩       调料

小题5:What is the main idea of the passage?

A.What passwords are.

B.How a password is hacked.

C.How to make your password much safer.

D.Why hackers hack your password.

单项选择题