Secret codes（密码）keep messages private. Banks, companies, and government agencies use secret codes in doing business, especially when information is sent by computer.

    People have used secret codes for thousands of years. {#blank#}1{#/blank#} Code breaking never lags（落后）far behind code making. The science of creating and reading coded messages is called cryptography.

    There are three main types of cryptography. {#blank#}2{#/blank#} For example, the first letters of “My elephant eats too many eels” spell out the hidden message “Meet me.”

    {#blank#}3{#/blank#} You might represent each letter with a number, for example. Let's number the letters of the alphabet, in order, from 1 to 26. If we substitute a number for each letter, the message “Meet me” would read “135520135.”

    A code uses symbols to replace words, phrases, or sentences. To read the message of a real code, you must have a code book. {#blank#}4{#/blank#} For example, “bridge” might stand for “meet” and “out” might stand for “me.” The message “Bridge out” would actually mean “Meet me.” {#blank#}5{#/blank#} However, it is also hard to keep a code book secret for long. So codes must be changed frequently.

A. It is very hard to break a code without the code book.

B. In any language, some letters are used more than others.

C. Only people who know the keyword can read the message.

D. As long as there have been codes, people have tried to break them.

E. You can hide a message by having the first letters of each word spell it out.

F. With a code book, you might write down words that would stand for other words.

G. Another way to hide a message is to use symbols to stand for specific letters of the alphabet.

How to develop courage by overcoming daily fears

    At times, when it comes to courage, we tend to believe it only applies to rare and uncommon situations. Yet our ordinary lives can also be full of courage, even if we are not facing the end of a gun, a wild animal or a dangerous criminal. Courage doesn't just mean doing heroic acts.{#blank#}1{#/blank#} In fact, where there is fear on a daily basis, there are opportunities for you to show your courage. Here are some suggestions to develop courage by overcoming daily fears.

    Recognizing your fears.

    By realizing that you're fearful, you are more likely to get to the bottom of what your fear is.{#blank#}2{#/blank#} You might come to understand that you're afraid of failing or taking chances. You may be fearful simply because you don't have confidence in yourself. The key is not to dwell on your fear, but rather to understand what it is that you're worried about.

    Ask yourself what is the worst that can happen.

    If you hesitate to take action, ask yourself this: what's the worst that can happen? Then prepare to accept it. Then go on to improve on the worst. Is failure the worst thing that can happen? No, absolutely not.{#blank#}3{#/blank#}. Doing nothing is actually the worst thing that can happen. When you take no action, you are assured of getting nowhere.

    Take action.

   {#blank#}4{#/blank#}  You cannot think courage comes just in one day. You need to act to overcome your fear. Your action may put you into discomfort, but you have to just do it. And your action can prevent you from being stuck.

    {#blank#}5{#/blank#} To build up your confidence, you need to do the same thing over and over again. Soon you will discover that less courage is needed because you have already gained mastery. You are able to move decisively forward.

A. Share your fears with others.

B. Practice, practice and practice.

C. So you are already in a comfort zone.

D. Courage comes from taking action

E. Each undesired result is just one more step towards your goal.

F. Finding out what is truly holding you back,

G. You needn't wait for an emergency to occur to develop courage.

A. Come in with something to say.

B. Prepare general comments.

C. Bring materials with you.

D. Don't make them wait.

E. Have no fear.

F. Go it alone.

    One of the best things you can do any time in the semester is go see the professor. So hoof on over to an office hour and have some one-on-one face time with someone who'll help you master the material and improve your grade, to boot. But how should you have this conversation with the professor? Here are five insider tips about how to make that office hour really count:

     {#blank#}1{#/blank#} No need to get all bent out of shape about going to see the professor. The professor would actually like to see you and answer your questions. Believe it or not, he or she is on your side and is eager to see you do well. And besides, he or she has seen many students stupider than you, so nothing you're gong to ask will set the record for stupidity.

    {#blank#}2{#/blank#} Even though you might feel more comfortable going with a friend or partner, the office hour will go better if it's just you and the professor. You'll get in more questions, the discussion will be tailored to what you need most help on, and two-party communication is almost always more productive than committee work. You friend can wait outside for the discussion.

     {#blank#}3{#/blank#} If you can't make the official office hours, most professors are willing to make individual, appointments to help you out. If you're lucky enough to land such an accommodation, though, be sure you're 100 percent on time. There's nothing that ticks off a professor more than making him-or herself available for a custom office hour only to find that you don't care enough to come on time. And besides, the professor might leave after ten minutes, which would make your trip a total loss.

    {#blank#}4{#/blank#} If you're meeting with the professor to go over a paper or test, or to ask questions about a particular lecture or reading, make sure you bring that paper or test, or your lecture notes or a copy of the article. The professor doesn't remember the comments he or she wrote on your individual piece of work—though he or she will be able to recall them after just a brief glance at your work. And if you have your lecture notes or the article in hand, you and the professor will be able to examine specific points that are confusing to you, rather than just talking in a general way about the contents.

    {#blank#}5{#/blank#} Office hours almost always go better if you bring a few specific questions to the meeting. It's almost never good to start a meeting with general comments such as: “I didn't understand what you said about [main topic of the course]”or “I couldn't understand any of your lectures last week.” Much better is to come in with two or three conversation-starters, about a specific concept, point, or problem you didn't understand. Keep in mind that in a fifteen-minute office hour (which is how long these things usually last), two or three questions are usually the most you'll have time to discuss.

                                                                     How to Grow Vegetables at Home

    Many people choose to grow their own vegetables for healthy food. You'll enjoy the fruits of your labor if you give your plants the care they require.

    Step 1

    {#blank#}1{#/blank#} Consider how much produce you can use. Also consider your space. Your gardening area will need at least six hours of sunlight per day.

    Step 2

    {#blank#}2{#/blank#} If the leaves are yellow or have holes that is a sign the plant is diseased. Look for plants with strong green stems and a shiny appearance.

    Step 3

    Prepare your soil. {#blank#}3{#/blank#} Add manure(肥料).

    Step 4

    Dig a hole as deep as the plant's root ball and a little wider. {#blank#}4{#/blank#}Checkthe instructions on each plant to see how much space to leave between plants. Water thoroughly(彻底地) when the planting is over.

    Step 5

    Maintain your vegetable garden by watering and weeding regularly. Your garden needs about an inch of water a week. {#blank#}5{#/blank#} Weed by hand or with a tool.

A. Plan your garden.

B. Consider the place.

C. Choose plants that look healthy.

D. Remove grass and weeds from the soil.

E. Place the plant in the hole and fill it in with dirt.

F. The biggest mistake is trying to do too much too soon.

G. Water once or twice a week to help your plants develop strong roots.

    Here are some easy steps for you to stay safe and secure on the Internet.

    {#blank#}1{#/blank#} Never give out your full name, address and phone number, unless it is a safe site or it is a well-known site.

    Protect your money. Do not give out your card information unless it is a secure site. You can tell if the site is safe by looking at the lower part of your screen.{#blank#}2{#/blank#} If it is locked, the site is secure. "Unlocked" means that you should not give a card number.

Don't believe "Get Rich Quick!". If it sounds too good to be sure— it is! If you get an e-mail that says you can make thousands of dollars in a few days, it isn't true. Most likely it will cost you in the end.{#blank#}3{#/blank#}

    A good virus scan (杀毒软件). Update your virus scan.{#blank#}4{#/blank#}When you buy a virus scan, it may have been on the shelves for months, so you need to update it frequently.

    {#blank#}5{#/blank#} Do not open e-mail attachments (附件) that are programs. Receiving these programs in e-mail is harmless, but opening and running them can be dangerous.

A. There is a small lock.

B. Stay away from these offers!

C. New viruses come out daily.

D. There are always some unsafe sites.

E. Keep your main e-mail address private.

F  Don't give out personal information.

G. Protect yourself from dangerous e-mail viruses.

    When you see cockroaches (蟑螂) in your house, your first thought might be to use a bottle of insecticide (杀虫剂). However, not only would your family be affected by harmful chemicals, but also it might not do much good. So researchers say that besides using chemical treatments, you can also use other methods like traps. {#blank#}1{#/blank#}. So, how do you do it?

    As with most insects, prevention is more important. {#blank#}2{#/blank#}. That means never leaving dirty dishes in the kitchen and sweeping the floor before you go to bed.

{#blank#}3{#/blank#}, so it's necessary to seal (密封) the entries into your home. This may take time, but in the end, it's worth the effort, especially if you live in an apartment and have neighbors who don't reach the same standards of cleanliness as you do.

    Keep your space as cool as possible. {#blank#}4{#/blank#}. They increase their activity level and even spread their wings and fly. With more heat they have more strength.

    You can also try turning to a natural insect control company. My insect control company uses diatomaceous earth, a kind of special soil, in the walls of my home.{#blank#}5{#/blank#}, it's not harmful for you and your family. Best of all, it works well.

A. Cockroaches can't go very long without water

B. Cockroaches can move through even the smallest spaces

C. Or you can give up chemicals and try just natural methods

D. When temperatures rise, many of these insects become active

E. Because the earth can cause an insect to die without the use of chemicals

F. You have cockroaches in the house, but you don't want to use insecticide

G. Make sure your house is clean, because food remains are attractive to cockroaches