Nowadays, more and more people like to shop on the Internet.  How can you protect yourself from different types of Internet tricks?  Following these tips can make you online shopping safer：
    (1) Never click on an unsolicited(主动提供的) e-mail.  If you are interested in the things well-known company that sells the same thing, don't click on any links in the e-mail itself.
    (2) Don't answer any e-mail that asks you for personal financial(财政的) information.  Most of the legitimate(合法的)companies will not ask your information through e-mail.  And don't believe what the e-mail says easily.  Sometimes some e-mail will ask you to make a telephone call to get more information about the things you want.  Don't forget to check the phone number on your phonebook to make sure it is the number of a legitimate company before you make the call.
    (3) When you are searching for information on the Internet, make sure that there is a key symbol at the bottom of your browser(浏览器)and the “http” in the website address.  These mean that the website is safe.
    (4) Don't sent your money to an unknown website before you receive the things they send to you and make sure they work well.
    Shopping on the Internet is convenient and fun.  It is also safe if you are careful enough.

“农为天下之本务，而工贾皆其末也。”与此指导思想相一致的是（  ）

在下列各句的空格内填上一个适当的完整的单词，该词的首字母已给出。
1. Tony is really p____. He keeps waiting outside the house for almost three hours.
2. The f____  stood on the board, laughing happily, because they caught lots of fish this time.
3. When I heard of my grandma's d____, I couldn't help crying.
4.Parents hope their children can do best in the class, so they usually e____  too much of their children.
5. There is nothing in the box. It's e____ 

市场上有时会有“问题藕”出售，“问题藕”貌似白嫩，但切开有一股难闻的酸味。用pH试纸测试，“普通藕”pH是7，而“问题藕”pH在3～4之间，估计含有硫酸或盐酸中的一种。究竟是什么酸呢?市场管理人员榨取了“问题藕”的汁液，然后用____   来鉴别，写出该反应的化学方程式：____ 。