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。
New parents who clean their homes very often1.（protect）their babies from bacteria and other organisms might want to cut back their efforts.
A new study suggests that high levels of contact with cleaning products are linked to2.increased risk of the childhood breathing condition3.（know）as asthma（哮喘）.
4.（researcher）asked a group of parents how often they used 26 common household cleaners during their babies’ first three to four months of life. By age three, the children who5.（come）in contact with cleaning products the most were 37 percent more likely to have asthma than children with the6.（little）contact.
The study also found that a lot of exposure to cleaning products caused children to be 35 percent more likely to have much difficulty7.（breathe）.In addition, they were 49 percent more likely to have certain allergies.
The leading researcher Tim Takaro told the Reuters news service he understands that parents want to make their homes safe8.their children. He said parents should read labels and look for products that are free of substances（物质）like9.（chemistry）colors and smells. Also, they should consider natural cleaning products instead of harmful10.
The holidays are simply the best time of the year._______, for those of us who use a wheelchair, there are some unique_______to be overcome when celebrating with family and friends.
When I was 13, I_______my neck in a car accident. Paralyzed（瘫痪）from the chest down, the_______weeks and months that followed were an unbelievable whirlwind（忙乱）of activity. Just days before the_______,the biggest challenge in my life was making sure to turn my homework in_______.
But in just an instant it all_______. My family and 1 were forced to_______surgical options, where to go for_______， and how to pay for everything. All the while, I was________as my world turned upside down. The________physical recovery center was several states away, so when holidays rolled around, taking a trip home to celebrate was near the________of our list. What I would come to learn is that a celebration with family was________what I needed.
My family surprised me with a________that Christmas. I couldn’t travel________, so everyone came to me and turned the small apartment in a________city into a warm home. They brought more food than anyone could hope to eat and plenty of________. More________, for the first time, I felt________again. All of a sudden I was sitting at the same kids’ table and laughing with my cousins like________had happened.
1.A.However B.Therefore C.Besides D.Still
2.A.fear B.shyness C.differences D.challenges
3.A.turned B.broke C.rubbed D.protected
4.A.previous B.casual C.immediate D.vacant
5.A.accident B.operation C.holiday D.examination
6.A.on earth B.on purpose C.on time D.on demand
7.A.improved B.changed C.mattered D.helped
8.A.make preparations for B.make commitments to C.make contributions to D.make decisions on
9.A.recovery B.occupation C.reflection D.exercise
10.A.relaxing B.appealing C.struggling D.hesitating
11.A.chosen B.finished C.abandoned D.known
12.A.top B.bottom C.back D.edge
13.A.hardly B.impossibly C.repeatedly D.exactly
14.A.prize B.victory C.party D.conclusion
15.A.abroad B.home C.alone D.outdoors
16.A.familiar B.native C.foreign D.strange
17.A.decorations B.fruits C.medicine D.homework
18.A.hopefully B.importantly C.successfully D.differently
19.A.smart B.ambitious C.normal D.healthy
20.A.something B.everything C.anything D.nothing
As the COVID-19 forces students to stay home, online learning has seen a sharp rise among students. Since late January, China has delayed starting the new school semester and encouraged students to study at home over safety concerns.
Besides what has been arranged by your schools as your study routine, what can you gain from online learning?1.
To successfully learn online, you need to dedicate a significant amount of your time, consistently attend the program, concentrate while studying and fully stick to your learning process, just as you would do for a regular course.
To stay on track with your online course, always keep in mind what you hope to complete by the end of it.2. Estimate how much time each task will take to complete. Keep detailed notes and review them often.
A study plan is important to online learning.3.Online learning needs to be well organized. Create a study calendar that will help you remember all the important dates like online exams or deadlines for your assignments.
When you feel yourself losing concentration, consider taking a short break or sopping for the night.4.
Taking online courses can be very convenient for many people.5.It requires time management skills, self-discipline, willpower and motivation.
A.Make a goal.
B.It can also offer you a good experience for self-learning.
C.Most importantly, you need to plan ahead with a good calendar system.
D.Online course companies also adopted special measures to meet students’ demands.
E.However, it may be challenging for some to successfully complete their online courses.
F.A to-do list is useful to carry out your study plan and to stay on track with your studying.
G.It is better to wait until you are able to start afresh rather than waste your time trying to focus.
You can’t see it with your own eyes，but your smart-phone is likely to be covered with bacteria- perhaps even more so than your toilet seat. That's a lot of dangerous microbes（微生物）floating around, and yes, it is terribly dirty.
In this age of global travel and trade, it’s more important than ever to cut down on possible routes of infection and to stop bacteria and viruses spreading from person to person. Part of that means making sure your phone isn’t sending anything more than data.
And besides the potential health risks of a dirty phone, there's also the simple annoyance of looking at a screen that’s covered in fingerprints and other oily spots that are part of life with a smart-phone.
In short, you’ve got plenty of reasons to regularly give your phone a thorough clean. Not just during a pandemic（大流行病），either-we should be thinking about keeping our phones bacteria free all the time, says microbiologist Paul Turner, a professor at Yale University.
After all, we touch our phones all the time and many of us are relatively careless about cleaning them. “It sets the stage for kind of concern,” Turner says. “People could be handling phones and picking up any bacteria or virus that can attach to a surface and survive for a period of time.”
Take SARS-CoV-2, the corona- virus（冠状病毒）that causes the COVID-19, for example. Scientists are still trying to get solid evidence, but early research suggests that it can survive on plastic or stainless steel（不锈钢）surfaces for two or three days. That means you could be washing your hands perfectly well, but immediately picking the virus up again as soon as you reach for your phone.
You could be doing everything right（like washing your hands and staying away from people），but
if there’s a contaminated surface in your home or your pocket, you could expose yourself to the virus anyway, Turner says.
1.Why does the author mention the toilet seat?
A.To draw a vivid picture of a dirty phone.
B.To show how dirty a toilet seat is.
C.To add some background information.
D.To introduce a topic for discussion.
2.What can we learn in Paragraph 6?
A.Simply washing our hands is not enough.
B.Scientists have got solid evidence of the COVID-19.
C.The corona-virus can survive on smooth surfaces for 2 or 3 weeks.
D.The author suggests washing our hands before using our phones.
3.What do the underlined words “contaminated surface” refer to in the last paragraph?
A.A stainless steel. B.A deadly virus.
C.A clean phone. D.An infectious phone.
4.What is the main idea of the text?
A.You may get infected with your dirty phone.
B.You are supposed to wash your hands.
C.You’d better clean your dirty phone.
D.You’d better throw away your dirty phone.
Seasonal pumped hydropower storage（SPHS），an already established yet infrequently used technology ,could be an affordable and sustainable solution（解决方法）to store energy and water annually, according to new IIASA research published in the journal Nature Communications. Compared with other mature storage solutions, such as natural gas, the study shows that there is considerable potential for SPHS to provide highly competitive energy storage costs.
Seasonal pumped hydropower storage means pumping water into a deep storage reservoir（水库）, built parallel to a major river, during times of high water flow or low energy demand. When water is not enough or energy demand increases，stored water is then released from the reservoir to generate electricity.
The new study is the first to provide a global, high-resolution analysis of the potential and costs for SPHS technology. In their analysis, researchers assessed the theoretical global potential for storing energy and water seasonally with SPHS, focusing on the locations with the highest potential and lowest cost. They found that the technology would be particularly effective in the Himalayas, the Andes, Alps，and the Rocky Mountains, as well as mountainous regions in the Middle East, Brazil, Asia, and Russia, and many other locations around the world.
The study also addresses some of the potential environmental concerns related to hydropower. Because SPHS reservoirs are deep and constructed parallel to, rather than within the course of a river, the environmental and land use impacts can also be up to 10 to 50 times smaller than conventional hydropower plants.
Hunt, lead author of the study, says, “With the need for a change to a more sustainable world with lower CO2 emissions（排放），renewable energies and energy storage will play a major role in the near future. Given the vast untapped（未开发的）and cheap potential of SPHS, it will soon play an important role in storing energy and water on a yearly basis.”
1.What is the strength of SPHS based on the new IIASA research?
A.It’s costly. B.It’s out-dated.
C.It’s rarely used. D.It’s inexpensive.
2.What do researchers concentrate on when assessing the use of SPHS?
A.Environmental protection. B.High profits.
C.Suitable places. D.Water flow.
3.What do we know about the SPHS reservoirs in Paragraph 4?
A.They damage the river.
B.They are environmentally friendly.
C.They are similar to traditional hydropower plants.
D.They can be effective in many places globally.
4.What’s the future for SPHS according to Hunt?
A.Promising. B.Panicking.
C.Discouraging. D.Demanding.
Sir David Attenborough is set to host a brand new natural history series, named A Perfect Planet. The noted documentarian is back, and will be starring in a five-part BBC One series which will take a look at “the intricate（复杂）systems” that allow Earth to boom.
The show is set to explain how the planet operates, looking at everything from ocean currents to solar energy to the weather, and risking all around the world, from India to the Arctic.
Plus, in showing how the earth works, the documentary will also seek to display how animals adapt to their natural environments as they continue to change. As ever, it sounds like a truly fantastic watch.
It won’t be a surprise to hear that the new Attenborough series is set to feature some wonderful film scenes, too.
Speaking of the brand new series, from Our Planet producers Silverback Films, Sir David said: “Oceans，sunlight, weather and volcanoes - together these powerful yet fragile forces allow life to flourish（茂盛）in astonishing diversity. They make Earth truly unique-a perfect planet. Our planet is one in a billion, a world filled with life. But now, a new determining force is changing the face of Earth: humans. To preserve our perfect planet we must ensure we become a force for good.”
While an exact first-show date has not yet been announced, the show is set to land on BBC One later this year.
1.What do we know about Sir David Attenborough?
A.He will direct the series. B.He will host a space series.
C.He enjoys a good popularity. D.He will explore all around the world.
2.A Perfect Planet covers the following EXCEPT______.
A.fantastic shots
B.performances of film stars
C.animals’ adaptation to environmental change
D.how the natural forces in the world work overall
3.In Sir David’s opinion, who/what is mainly responsible for changing the face of the planet?
A.Man. B.The animal.
C.Climate change. D.The power of nature.
4.In which part of a website will you find the text?
A.Health and Lifestyle. B.Sports and Games.
C.TV and Films. D.Fashion and Beauty.
