阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。
Litter is everywhere，doing great harm 1. the environment and life on our planet.Jeff Kirschner，who wants to build a litter-free world，started a global community named Litterati 2. (settle)this problem.
The story began with his 6-year-old daughter.One day they were going on a hike when the girl noticed a 3. (break)plastic tub(浴盆)in a river.She said，“Daddy，that doesn’t go there.”That took Kirschner by surprise.He，like many adults，had become so used to the rubbish around them that he hadn’t given it a second look.4. his daughter said reminded him of the serious problem our planet faces.
Jeff started to take 5.(act).He created Litterati，an app that makes it fun to pick up litter.The idea is 6.(fair) simple:Spot a piece of trash，take a photo，post the photo online and then put the litter into dustbins.
7. (see)that Jeff was keeping a record of the positive impact he was having on the planet，people worldwide started participating.Up to now，over 2，500，000 photos posted by 3,500 people from over 40 countries 8. (find)their way to Litterati’s digital landfill.
Litterati is more than an app.It is a highly 9. (effect)solution to a pressing issue.Wherever you live，whatever you do and 10. you are，join Litterati to make the world a cleaner and healthier place to live in.
I grew up with two elder sisters.If I wasn’t courteous(礼貌)to them，they’d fix me.So courtesy wasn’t really ____ in my childhood home.
My sisters ____ every chance to train me how to be a courteous ____ .They made me open doors for them or help them into their ____ at dinner.
Years later I went away to college.The first time I walked into the library，I noticed a woman walking behind me and I ____ the door open for her.
___ ，she glared at me，asking loudly，“Do you think that because I’m a woman I'm not ____ enough to open a door for myself ?”She slammed(摔)the door shut，leaving me astonished and ____ .My face burned with ____ .I decided ____ that there would be no more courtesy!
As I stood there，another lady ___ the door，her arms ____ with textbooks.Instinctively(本能地)I __ to open the door for her. ____ I realized what I had done.I prepared myself for shouts.However，I received a warm smile and a look of __ .
“Thanks!”she said brightly.“It’s nice to see we still have a few gentlemen around here!”
Of course，if I were REALLY a gentleman，I would have ____ to help with her books.Despite this，I appreciated the good ____ I got from performing all act of simple courtesy.To do otherwise would be to ____ my lifetime of training.
Courtesy brings pleasant，refreshing light to our lives whether we are the giver，the ____ or just an interested observer.Courtesy doesn’t ____ change our lives，but it can certainly transform the way we feel about life.
1.A. important B. available C. delightful D. optional
2.A. made the most of B. got ready for C. gave way to D. put forward
3.A. colleague B. assistant C. companion D. gentleman
4.A. dresses B. chairs C. dishes D. mouths
5.A. answered B. unlocked C. held D. forced
6.A. Instead B. Even so C. Unexpectedly D. Sure enough
7.A. strong B. confident C. courageous D. experienced
8.A. impatient B. speechless C. anxious D. desperate
9.A. fear B. excitement C. embarrassment D. envy
10.A. in advance B. in a flash C. once more D. by chance
11.A. approached B. passed C. pulled D. entered
12.A. surrounded B. crowded C. covered D. overloaded
13.A. regretted B. refused C. reached D. hesitated
14.A. Until B. Although C. In case D. The moment
15.A. doubt B. relief C. guilt D. curiosity
16.A. offered B. agreed C. promised D. waited
17.A. thought B. process C. feeling D. advice
18.A. correspond with B. 1ead to C. go against D. hold on to
19.A. judger B. receiver C. loser D. reporter
20.A. necessarily B. normally C. casually D. naturally
For the first time in 10 years，the United States government has changed its guidance on how much exercise people need to stay healthy and when they should start.
For children and teens
The new guidance states that the most important time for children to begin exercising is between the ages of 3 and 5. 1. That could be light activities，moderate activities，or even vigorous(剧烈的)activities.
Doctors say it is important to start young.They add that from birth to age 5，a child’s brain develops more than at any other time in life. 2. Also，children who start exercising at a young age are more likely to establish healthy behaviors they will continue into adulthood.
But that does not mean putting a small kid on a treadmill(跑步机)or other exercise equipment. 3. After all，it's a kid’s nature to play freely and happily.
4. But it shouldn’t be less than one hour a day three times a week.Their activities should mostly be aerobic(有氧的)exercise，such as biking，swimming or running，which can strengthen the heart and lungs.Such exercise should also include muscle-and-bone-strengthening activities；such as climbing trees or playground equipment and playing sports.
For adults
For adults，the guidelines recommend exercising 150 minutes a week.That could be walking，gardening，dancing，etc.5. Experts say that even short amounts of aerobic exercise can provide health benefits，such as lowering blood pressure，reducing anxiety and improving sleep.
A.Any kind of activity that gets people exercising will do.
B.Aerobic activity works only if it lasts for at least 10 minutes.
C.Simply giving a kid the time and space to play actively is enough.
D.Children above 5 can have a relatively shorter time for daily exercise.
E.Children in this age range require about three hours’active activities daily.
F.Attaining the health benefits from exercise may be harder than earlier thought.
G.These developments have a 1asting effect on a child’s ability to succeed in life.
The Broadcom MASTERS competition aims to find a balance between celebrating individual accomplishments and acknowledging that science seldom happens alone.The competition takes off when students from around the country are teamed up and have to solve a series of hands—on challenges in the spotlight.
Nowadays，kids are fed with“the myth of the lone scientist”，so placing such challenges in the middle school period has a huge potential for impact.The focus on teambuilding skills gets students excited before more fears and stereotypes(成见)set in.
The initial pool of qualified students comes from the participants in nation-wide science fairs.Those who score in the top 10％(about 1 0，000 kids)have the qualification to apply.The judges select the top 300 young scientists，and that group is finally narrowed to 30 finalists.
Selection at this stage is clearly an honor in itself，but it counts as step one for the finalists.They are then flown to Washington，D.C.and placed into teams of five for the hands-on part of the competition.Each team is made up of students with different talents and skills，including academic focus and experience.
Unlike the science fairs，where most of the work takes place behind the scenes and students share a polished outcome，the hands-on challenges create a space where the work is the competition itself.The students take up a range of challenges in science，technology，engineering，math and so on.Each of the challenges will need the insight and skills of multiple team members.
Judges observing the challenges aren’t just looking for outcomes but also for leadership，teamwork and problem solving.
The Broadcom MASTERS attracts increasing numbers of passionate and talented young people who are eager to take part in a program that helps them grow as scientists，engineers and inventors.It lets the students experience a sense of coming together with true peers.More importantly，it provides them with new skills to tackle future challenges.
1.What does the Broadcom MASTERS competition mainly focus on?
A. Individual accomplishments. B. Hands-on challenges.
C. Academic performance. D. Team work.
2.What does Paragraph 3 mainly tell us?
A. A large number of kids take part in the science fairs.
B. It’s not easy to be qualified as a member of the finalists.
C. The judges are too strict with the participants.
D. The nation-wide science fairs are well organized.
3.What can we infer from the text?
A. The Broadcom MASTERS competition has an increasing impact.
B. Middle school students prefer to challenge each other.
C. Students can learn more new skills from the Broadcom MASTERS.
D. The science fairs will be completely replaced by the Broadcom MASTERS.
4.What can be a suitable title for the text?
A. Learning to Take on Scientific Challenges
B. Outstanding Students are Publicly Honored
C. Bringing Individual Potential to a Team Opportunity
D. The Science Fair:A Platform Where Students’Dreams Take off
America’s latest superhero Austin Perine，who calls himself President Austin，is now taking the country by storm.But he is not a typical superhero.Two things set him apart:He doesn’t fight human enemies，but hunger and homelessness.Also，he’s only four years old.
Our superhero’s origin story started from the day when TJ Perine，his father，took Austin to the Firehouse Ministries，a local shelter that provides housing，food and other services for the homeless.As they drove by the building，they saw a group of 25 homeless men standing on the street corner.That day，Austin used his allowance to buy each man a sandwich and handed the food out himself with his slogan，“Don’t forget to show love!”
After he returned every week for five weeks in a row，word of Austin’s kindness spread through social media.Austin and TJ could feed 25 to 50 people at a time before，and now，thanks to community support，they can feed 800 to 2,000 people.
But Austin isn’t merely filling stomachs.He has been improving the lives of the homeless people he meets.On that first trip to Firehouse Ministries，TJ and Austin talked to a poor man named Raymont.The respect Austin showed for him touched 41-year-old Raymont，who regained his confidence in life and finally found a job with the help of TJ.All that was made possible because a little boy took the time to care.
Austin’s passion has become his family’s calling.After raising money through a GoFundMe page，Audrey，TJ’s mother established the nonprofit Show Love Foundation，dedicated to fighting homelessness. She now serves as president，and TJ oversees public relations for the foundation full time.They offer medical and mental health care as preventive steps against homelessness.
As for President Austin，he continues to give out food，smiles，and his inspirational message of love.“It makes me feel like I’m saving the day,”he said proudly.
1.Why has Austin become well—known to the entire country?
A. He has super power to fill the stomachs of the homeless.
B. He fights hunger and homelessness at such a young age.
C. He has removed the poverty of the local community.
D. He has chosen an impressive and unique name.
2.Which of the following can replace the underlined word“dedicated”in Paragraph 5?
A. Exposed. B. Opposed. C. Devoted. D. Addicted.
3.Why does the author introduce the example of Raymont in Paragraph 4?
A. To show Austin’s positive influence.
B. To persuade people to live off their own.
C. To prove the personal ability of Austin’s father.
D. To describe the difficult situation of poor people.
4.What is the author’s attitude towards what Austin does?
A. Sympathetic. B. Humorous. C. Approving. D. Considerate.
Feeding birds is a popular way to watch wildlife.But experts say it might put wild birds at risk.
Feeding birds is not necessary for their survival except in extreme weather conditions.Feeders(喂食器)can definitely help birds get through that kind of weather.But most birds eat insects and show little interest in bird feeders.For those birds，we can grow native plants in a natural environment.Birds which are fond of eating seeds will be more likely to come to feeders if there is some cover nearby.This lets them feed and then fly to protective areas，such as in trees.
The most common mistake people make with their bird feeders is that they put feeders in places where birds are easily frightened by passers-by，risk being hurt by cats，or risk flying into windows.
So set up a bird feeder at least one meter away from a window.That way，if a bird gets frightened，it won’t get killed when it hits the glass.Owners of cats should keep them inside home so they can’t hurt the birds.
Some birds are more aggressive at feeders.They eat a lot and do not leave much food for other birds.A solution is to put the food in more than one place by using different kinds of seeds or fruits.This can also increase the number and diversity of birds in your neighborhood.But don’t feed wild birds anything salty，like potato chips，or food that could choke them，like bread.
Pay attention to food quality and freshness.Unprotected food left too long in feeders will turn moldy(发霉)，which can kill wildlife.
Another word of advice:Always provide a supply of clean water for birds，but use care when looking for the right birdbath.If the birdbaths are too deep for birds，putting a few large stones in the water can give the birds a place to sit.
1.What’s the most common mistake about feeding birds?
A. Putting feeders in improper places. B. Providing food in inappropriate time.
C. Leaving feeders unprotected. D. Supplying dirty and deep water.
2.Which of the following may not be suitable for feeding birds?
A. Seeds. B. Bread. C. Fruit. D. Insects.
3.The author advises helping more birds by_________.
A. increasing the number of feeders
B. cleaning the birds with clean water
C. putting more large stones in the feeders
D. keeping aggressive birds away from the feeders
4.What is the text mainly about?
A. Problems with bird feeding.
B. Where to place bird feeders.
C. Popular ways of protecting wild birds.
D. How to feed wild birds safely and healthily.
