一、完形填空（10分）
At Beijing Chaoyang Railway Station, Cao Yan leads a service team to help passengers in need. Her team offers timely help and guides passengers orderly in the crowded station, which 1 Beijing with North and North-east China.
The team always keeps 2 when dealing with all kinds of emergencies. People can turn to them for help online, and the team never puts off any useful service.
Cao takes her 3 seriously. Before forming groups, she will 4 each member's strong points and train them carefully. They follow strict rules, but they treat every traveller sincerely.
Starting railway work in 2007, Cao kept learning all route（路线）information day after day, and her great efforts 5. People even praise her as a "living map". Gradually, more people join the team to provide service.
6 Cao has to miss dinners with her family on festivals, she never regrets her choice. She thinks her work is really 7. Helping others brings her a strong sense of happiness. She used to be a soldier. She knows clearly 8 she should stick to her original heart（初心）.
Most passengers speak highly of their service, but few people fully know how much 9 they have made. 10 what challenges they meet, they are ready to face them bravely and offer "may I help you" at all times.
() 1. A. connects B. follows C. divides D. communicates
() 2. A. silent B. patient C. proud D. modest
() 3. A. level B. position C. spirit D. chance
() 4. A. consider B. explain C. doubt D. refuse
() 5. A. came out B. took place C. paid off D. ran out
() 6. A. Unless B. Though C. Since D. Until
() 7. A. valuable B. casual C. strange D. relaxing
() 8. A. how B. whether C. that D. when
() 9. A. time B. pain C. effort D. kindness
()10. A. Even if B. In case C. As well D. No matter

二、阅读理解（16分）
A
Time flies when you have fun on your smartphone. But when you sit down to work and study, an hour feels like a year. ▲ It is all because of something small called dopamine which is a "joy chemical" that makes people feel good. Our brains（脑）release it when we eat yummy food, after we exercise or when we are praised.
Compared with studying, eating chocolate can make your brain release 150% more dopamine, and exercising for 30 minutes raises it by 200%. But using smartphones creates much more dopamine. For example, watching short videos gives a 250% increase, and checking new messages makes dopamine jump by 400%—much higher than studying. But why? When we go through social media, we don't know what we'll see next. This uncertainty makes dopamine active. Studying doesn't provide such uncertainty. Without the excitement of "gambling（赌博）", we get bored much more easily.
Can we do something to change that? According to research, apps can become less attractive if we turn off notifications（消息通知）or change the screen colours to black and white. We can also set time controls on apps. As for studying, you could check your progress daily or weekly and reward yourself for it. You could also explore interesting topics related to your textbooks.
（）1. Which of the following can be put in "▲"?
A. Why is studying so important for our brains?
B. Why are we so easy to be tired of using smartphones?
C. Why is using a smartphone the best way to improve study?
D. Why are we so crazy about smartphones but easily bored with studying?
（）2. What does the underlined word "release" mean in the passage?
A. Recycle. B. Reduce. C. Produce. D. Attract.
（）3. Which of the following pictures shows the level of dopamine increase?

（）4. What can be the best title for the passage?
A. The Joy Source of Life: Dopamine B. The Cure of Screen Habit: Phone Tips
C. The Fun-Killer of Study: Dopamine D. The Cure for Boredom: Learning Plans
B