How confident she looks! She________be ready for the competition.

A.need B.must C.can D.would

練習冊系列答案
相關習題

科目：初中英語 來源：2020年6月江蘇省常州市九年級第二次教學情況調研測試（二模）英語試卷 題型：單選題

Beyond ________stars, the astronaut saw nothing but _______space.

A./; the B.the; / C./; a D.the; the

查看答案和解析>>

科目：初中英語 來源：2020年山東省濟南市章丘區(qū)中考三模英語試卷 題型：單選題

There will be heavy rain and strong wind next ___________ / wi:k /.

A.week B.wait C.west D.weak

查看答案和解析>>

科目：初中英語 來源：2020年北京市西城區(qū)中考二模英語試卷 題型：閱讀單選

Bacterial Quorum Sensing

Bacteria(細菌)play an important role in our lives. They can keep us alive as well as make us sick. It wasn’t until fairly recently that we learned bacteria can communicate with one another.

In the 1960s, researchers found that a kind of bacteria called Vibrio fischeri（費氏弧菌） produced no light when they were alone, but that they exhibited great amount of light as the bacterial population grew to a certain number. How did this happen? How can Vibrio fischeri tell the difference between times when they’re alone and times when they’re in a community, and then all do something together?

Researchers found they talk to each other with a chemical language—signal molecules(信號分子). Vibrio fischeri makes signal molecules, and it also has a receptor on its surface that fits like a lock and key with a signal molecule. As the bacteria increase, more and more signal molecules are sent into the environment. When signal molecules increase to a certain amount, they lock down into those receptors and information comes into the bacteria, which tells them how many neighbors there are. As soon as they realize the population has hit the certain number, all of the bacteria behave as a group, making light together. In the past ten years, researchers have found all bacteria have systems like this: they make and recognize chemical words, determine(判斷)the size of the community, and carry out tasks that would be unsuccessful if a single one were to act alone. This process is called quorum sensing.

Most of the time, bacteria live with thousands of other species (種類)of bacteria. There has to be a language of interspecies communication. In fact, bacteria have another kind of signal molecule, which is the common language used by all species. Moreover, this kind of molecule has its own receptor. In this way, bacteria are able to count different populations, and then they decide what task to carry out depending on which species has the greatest population.

Knowing how bacteria communicate could influence how we fight disease. What if bacteria can’t talk or hear? They won’t recognize when there are enough bacteria and when to exhibit the group behavior to make us sick. Researchers are developing a method—to make molecules that look like the real ones and then they lock into the receptors to jam recognition of the real situation.

On the other hand, researchers also improve the conversation of the beneficial bacteria, so they can do things that we want them to do better than they would do on their own.

1.According to the passage, what can we learn about quorum sensing?

A.Quorum sensing may happen when there is only one Vibrio fischeri.

B.Signal molecules are kept away from receptors during quorum sensing.

C.Most bacteria have similar systems to make light during quorum sensing.

D.Bacteria carry out a group task when their population hit a certain number.

2.What can we learn from the passage?

A.The more species there are, the more group actions bacteria will take.

B.In different environments, bacteria have different interspecies languages.

C.Beneficial bacteria communicate better by themselves than harmful ones.

D.To fight disease, researchers try to turn off the communication between harmful bacteria.

3.The passage is mainly about ________.

A.why bacterial population grows B.how bacteria communicate with each other

C.which bacteria help fight disease D.what scientists do to find quorum sensing

查看答案和解析>>

科目：初中英語 來源：2020年北京市西城區(qū)中考二模英語試卷 題型：單選題

Tony and I________table tennis once a week. He plays better than I do.

A.play B.will play C.played D.have played

查看答案和解析>>

科目：初中英語 來源：湖南省2017-2018學年八年級上學期期末英語試卷 題型：語篇翻譯

Here's all of the information you need to write on your party invitation. If it shows all of the facts about your party, 1.客人們將會覺得更容易做決定。They will be clear about if they can accept it or they have to turn it down.

The first thing you should put on your invitation is the name of the party host and the theme (主題) of the party. Your invitation should show the type of the party to the persons that you want to invite.

2.The next is the place where the party will be held. If your guests don't know about the address of the party, they may check the way to go without getting lost.

3. Clearly write the time of your party, with both date and day of the week. After checking the calendar, the guests will know if they are available on that day. 4.Your invitation also needs to tell your guests what time to arrive and how long the party will last (持續(xù)).

If you want your guests to reply to your invitation as soon as possible, you can give them a date by which you'll need an answer. 5.并且告訴他們一個電話號碼或者一個電子郵箱地址 so that they can let you know.

1.______________________________________________

2.______________________________________________

3.______________________________________________

4.______________________________________________

5.______________________________________________

查看答案和解析>>

科目：初中英語 來源：湖南省2017-2018學年八年級上學期期末英語試卷 題型：完型填空

Hong Kong is a city that's full of surprises. 40% of the land________ beaches, woodlands (林地) and mountains. Hong Kong is a water city ______ different islands, and kids will have fun_________boats everywhere.

You can also________a lot of nice food there. You can walk into Dim Sum restaurants at any time. They are always ________, noisy and full of families. After you sit down at a big round table, you may_______ for waitresses to come with ________dishes. As they come by, tell them the dishes you want. The waitress will put the dishes down on your table. Keep asking for dishes until you are________ .

Hong Kong has________ shopping areas, and the Jade (玉) Market in Kowloon is a good place. Here, you can_________ jade earrings, jewelry and carved (雕刻的) animals, such as tigers and dragons.

1.A.is B.are C.was

2.A.at B.of C.with

3.A.going B.taking C.riding

4.A.cook B.eat C.make

5.A.busy B.free C.quiet

6.A.stop B.wait C.look

7.A.same B.terrible C.different

8.A.full B.hungry C.thirsty

9.A.many B.much C.a little

10.A.get back B.leave for C.find

查看答案和解析>>

科目：初中英語 來源：2020年吉林省長春市汽開區(qū)中考一模英語試卷 題型：閱讀單選

We spend hours, days and years of our lives in school. Imagine you could design（設計）your dream school, what would it be like? What would you be doing? We wanted to find out what teenagers around the world thought.

Here is what they said:

Richard from the USA: My dream school would have a big swimming pool. It would also have a cinema, a gym and a shopping center. My school has none of these and I think there should be more pleasant things for students to do while they are studying.

Sonia from Italy: I’d like a room where we can relax and play computer games. I’d also like to have a music room. I think there should be a place for everyone to go and relax after class.

Wu from Beijing: I think it would be great to have another day off every week, besides the weekend. If that day was a Friday or a Monday, we would have a long weekend every week. What fun! I also think school should start later, at about 10 o’clock, and finish earlier.

Hannah from Australia: In my dream school, I think the teachers should give us more freedom and choice about how we study and what we study. I also think it’s not necessary for us to wear school uniforms every day. I really don’t like wearing it.

根據(jù)材料內容，選擇最佳答案。

1.There would be __________ in Richard’s dream school.

A.a big swimming poor and a music room

B.a room to relax and play computer games

C.a long weekend, three days off every week

D.a big swimming pool, a cinema, a gym and a shopping center.

2.Wu wants to have ____________ days off in a week.

A.2 B.3 C.4 D.1

3.The country of ___________ is NOT mentioned in the passage.

A.Italy B.Australia C.Japan D.USA

4.In ___________ dream school, the teachers should give them more freedom and choice for study.

A.Richard’s B.Sonia’s C.Wu’s D.Hannah’s

5.From the passage, we know that __________

A.Sonia from Italy would like a room where she can relax and play computer games

B.Richard from the USA think his dream school should start at 10 o’clock

C.Wu from Beijing thinks it would be great to have two days off every week

D.Hannah from Australia likes wearing a school uniform every day

查看答案和解析>>

科目：初中英語 來源：2020年天津市和平區(qū)中考三模英語試卷 題型：單選題

There was a heavy traffic. ________, I was late for the meeting.

A.As a result B.At first C.As well as D.For example

查看答案和解析>>

同步練習冊答案