根据短文内容，从短文后的选项中选出能填入空白处的最佳选项，选项中有两项为多余选项。

      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 threemain 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 “13 5 20 13 5.”

     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.

    Moving to a new place may be an exciting adventure.{#blank#}1{#/blank#} If you have a friend experiencing this anxiety, there are some steps you can take to make him feel more at home. Talk to your friend about his homesickness.{#blank#}2{#/blank#} This also gives you the option to share with him any strategies you have personally discovered to help overcome these feelings.

    Join your friend in discovering and adapting to the new environment. It is human nature to fear the unknown. By learning to deal with the new environment, your friend will find it easier to overcome the desire for what is familiar.

    Introduce him to new friends by including him in your social circle. These new relationships help relieve the feelings of homesickness and keep his mind off those friends he left behind.{#blank#}3{#/blank#} For example, if he likes sports and being outdoors invite him to go hiking or camping with you and your friends.

{#blank#}4{#/blank#} Developing a new schedule will help him change things to where he does not need his old routine. Perhaps get him involved in an athletic club where he can boost endorphins(内啡肽) by keeping physically fit.

    Keep a positive outlook. Encourage him to see the glass half full so he can embrace this new experience instead of longing for what once was. Being positive helps your friends become more positive, so make the most of your influence{#blank#}5{#/blank#}

A. However, there are many ways to overcome it.

B. Burying it will only make his homesickness worse.

C. Invite him to clubs that you know he will enjoy.

D. Help him develop a new routine to replace the old one.

E. You will help him keep an active attitude to life if you are positive.

F. He could be homesick due to missing family dinners every night

G. However, following that is the anxiety that comes from a change in routine.

Taking Care of Your Health While Traveling

    When you're often on the go, it is likely that your health will suffer. Here are a few simple ways you can keep on top of your health.

    ⒈{#blank#}1{#/blank#}.

    When you're travelling, your body will quickly begin to wear down. How much is enough sleep? It all depends on your body-listen to it.{#blank#}2{#/blank#}. Although you want to experience as much as possible when travelling, it is still important to rest.

    ⒉Don't forget to take plenty of water.

    Carry a water bottle with you everywhere and keep it filled up with fresh water. {#blank#}3{#/blank#}, it will do your body a lot of good and keep you feeling your best.

    ⒊Eat healthier.

    {#blank#}4{#/blank#}. Yes, we get that you are on your holidays, but healthier choices will keep your body filled up with nutrients, which will make you feel better in the long-term.

    Make your own meals.

    Eating out each day isn't healthy for you so you should try and make your own meals where possible. {#blank#}5{#/blank#}, but making a few healthy sandwiches in your hotel room is something you should be doing.

A. Get plenty of good sleep

B. Take a break before you wear down

C. Try and cut out as much sweet as possible

D. If you pace yourself and go about things slowly

E. Even if you need to visit the bathroom more often

F. It is difficult to go to the bathroom when travelling

G. We're not talking about coking up a three-course meal

Being a superhero to others

    Ewan Drum has always liked superheroes. He likes how they help people. At age seven, he told his parents, “I want to dress up like a superhero and help the homeless.” {#blank#}1{#/blank#}Wearing his red superhero cape (斗篷), Ewan helped pass out  bag lunches to hungry people in a park in Detroit, Michigan. That's how Super Ewan was born.

    {#blank#}2{#/blank#}People donated(捐赠) money and supplies (供给物), and Ewan took them to those in need.

    When someone donated jugs(大罐) of water, Ewan and his family drove their car to get even more. They took the water to Flint, Michigan, a city that had unsafe drinking water. Another time, a businessman donated six turkeys(火鸡) for Thanksgiving.{#blank#}3{#/blank#}“In the end”, he says, “we gave turkey dinners to families all around Detroit.”

    Ewan has a motto: Everyone can be a superhero to someone. At an event called the Hero Round Table, Ewan told the audience, “It's not hard to help people. You can keep some socks and food in your car to help people in need. You can help a neighbor with doing the garden. {#blank#}4{#/blank#} ”

It's been several years since Super Ewan started his task. Every month, he still visits the same park to hand out clothes, food, and supplies to people who are hungry or homeless —his Super Friends. {#blank#}5{#/blank#}

    “No matter what,” Ewan says, “I will always keep helping people.”

A. News spread about Ewan's act of kindness.

B. This superhero says he'll never take off his cape.

C. Ewan says he wants more adults to act like superheroes.

D. Every little thing helps and can make someone feel happy.

E. A few months later, Ewan's family planned a day of giving.

F. Several days later, his parents drove to Flint and helped him raise a lot of money.

G. With his parents help, Ewan asked for more turkeys through the Internet, plus side dishes.

    After a long day at work, coming home is a breath of fresh air. Home is a comfortable place to sit back and relax. {#blank#}1{#/blank#} Below are a number of things we can do to create a healthy home environment that will help to ease the workday stress and promote our physical and mental health.

    Cleaning the house regularly is the first thing we should do. It may seem like a tiring thing to clean but there is a reason for doing so. We can remove dust by cleaning the house. Leaving layers of dust everywhere means that there is a build-up of dust. And where do these layers of dust go?{#blank#}2{#/blank#}

    Making sure the rooms are full of sunlight is also important. We may not realize it but sunlight is an important part of our growth. We all know that sunlight promotes better working conditions. {#blank#}3{#/blank#} Think about using a Parans system where sunlight does not reach. This technology gathers the sunlight by using solar panels. It can send out sunlight wherever we are.

    {#blank#}4{#/blank#} Going green will help to remove toxins(毒素)in the air. They also give off oxygen, which can lower stress and improve our moods.

Along the lines of being green, it can also be vital to think about what things we are bringing into the house. Try to avoid specific plastics that are harmful to health. {#blank#}5{#/blank#} They may contain poisonous chemicals that can be breathed in, or simple absorbed through the skin.

A. Into our lungs.

B. However, is it as healthy as it can be?

C. Is our home as comfortable as it used to be?

D. It is also a good idea to add more plants in our house.

E. The same thing applies to things like carpets and paint.

F. Besides, it can reduce both stress and high blood pressure.

G. It is acknowledges that a greener lifestyle is linked to better health.

Walking has been considered as one kind of rewarding exercise. For many people, daily walking offers massive and long-term physical and mental benefits. {#blank#}1{#/blank#} A Stanford University study found that participants were more creative when walking as opposed to sitting. 

{#blank#}2{#/blank#} You've probably heard the phrase "exercise your creativity". Our creative mindset is stirred up by physical movement, which is exactly why walking with your dog, a friend, or alone feeds creative thinking. 

But the scenery is almost as important as the sweat. Just by going outside, you are stepping out of your habitual surroundings and your comfort zone, which is necessary if you want to open your mind to new possibilities. You can walk through a tree-filled neighborhood. {#blank#}3{#/blank#} Even when you walk down a busy street, you can't help but get distracted by the sweet smells from a food cart or the child pointing to a building you haven't even noticed before. 

Walking outside develops our ability to collect new ideas and take in new sights, sounds, smells, and flavors. Shinrin-yoku, a common form of relaxation in Japan, suggests that being in the forest and walking among the trees there can lower your stress levels. {#blank#}4{#/blank#} Research has shown that getting close to nature around your neighborhood or taking a break from multimedia increases performance on a creative problem-solving task. 

So instead of setting a fitness goal, why not set a creativity goal that starts with walking outdoors? {#blank#}5{#/blank#} For example, you can turn off your phone and give yourself the chance to be present in the world, to hear conversations and natural sounds, and to notice the way people move and the way the sun reflects in a lake. 

Walk not just for exercise. Walk for wonder.

A.Unfortunately, you often fail to do it.

B.Expose yourself more to your surroundings.

C.The movement during walking is obviously key.

D.Without enough energy, you cannot wonder or create.

E.But to receive the benefits, you do not have to live in a forest.

F.This habit, however, not only benefits well-being but also contributes to innovation.

G.Wandering around a park and observing people relaxing or birds singing is also a choice.