In its early history, Chicago had floods frequently, especially in the spring, making the streets so muddy that people, horses, and carts got stuck. An old joke that was popular at the time went something like this: A man is stuck up to his waist in a muddy Chicago street. Asked if he needs help, he replies, "No, thanks. I've got a good horse under me."

    The city planner decided to build an underground drainage (排水) system, but there simply wasn't enough difference between the height of the ground level and the water level. The only two options were to lower the Chicago River or raise the city.

    An engineer named Ellis Chesbrough convinced me the city that it had no choice but to build the pipes above ground and then cover them with dirt. This raised the level of the city's streets by as much as 12 feet.

    This of course created a new problem: dirt practically buried the first floors of every building in Chicago. Building owners were faced with a choice: either change the first floors of their buildings into basements, and the second stories into main floors, or hoist the entire buildings to meet the new street level. Small wood-frame buildings could be lifted fairly easily. But what about large, heavy structures like Tremont Hotel, which was a six-story brick building?

    That's where George Pullman came in. He had developed some house-moving skills successfully. To lift a big structure like the Tremont Hotel, Pullman would place thousands of jackscrews (螺旋千斤顶) beneath the building's foundation. One man was assigned to operate each section of roughly 10 jackscrews. At Pullman's signal each man turned his jackscrew the same amount at the same time, thereby raising the building slowly and evenly. Astonishingly, the Tremont

    Hotel stay open during the entire operation, and many of its guests didn't even notice anything was happening. Some people like to say that every problem has a solution. But in Chicago's early history, every engineering solution seemed to create a new problem. Now that Chicago's waste water was draining efficiently into the Chicago River, the city's next step was to clean the polluted  river.

    A new camera made by a company named Netatmo has facial recognition software(识别系统)that can tell parents at work that their children have returned from school, or that a package has been taken to their home. It can also tell them if a stranger has entered their home.

    Janina Mattausch is a product marketing manager for Netatmo.

    “The common security(安全)cameras at present are not that smart. So, they can tell you if something is moving but they don't necessarily know if it's a human being or, ah, if it's your kids—they don't' know the difference, so they will warn you all the time.”

    When family members enter a home,  the new camera "recognizes" (识别 )  them and sends information to the owner's smartphone. The owner can choose to see the video then or later.  But if an unknown person enters a home, the camera will send the owner a warning that will cause an alarm to sound on the owner's smartphone.

    That is what happened recently to a smart home camera owner named Darrmen. He lives in Paris.

    "On a Friday I was at work, attending a big monthly meeting when my phone warned. At first I told myself 'Oh, it must be a mistake, maybe I have to set the system again. “But the notice on my phone was telling me that there was a movement in my flat and also a face that the software did not recognize.”

    He watched the video and was very surprised by what he saw.

    "I saw a person I did not know with his shoes on. I was watching it live on video. So I felt totally unbelievable, frozen. I asked a workmate to take me back home as fast as possible and I called the police on the way. "

    With the help of the video,  the police found the intruder (闯入者) later that day.

根据短文内容，选择最佳答案，并将选定答案的字母标号填在题前括号内。

    In order to change the way Americans think about their trash footprint, Rob Greenfield is going to live like the average American for one month. He'll eat, shop, and consume just like the average American who14.5 pounds of trash per day. He has to2every piece of trash he creates. That's nearly 140 pounds3the end of the month(almost his body weight)! Every coffee cup, plastic bag, pizza box, every single piece of trash be creates will be on his4, everywhere he goes.

    The idea behind Bob's “TrashMe” project is to show people the5effects of trash. Most people6think about how much waste they are producing every month. They just7their garbage bags, put them in the bin and8someone to pick them up. But what if they came face to face with a walking, talking9of overconsumption? That might get them thinking about the world's10trash problem and maybe even get them to11the amount of trash they generate.

    To make himself12to a wider audience, Greenfield has13a nonprofit film studio LivingOne to create a six-episode TrashMe web-series. He promised to deliver “a visual of14that Americans will never forget.”

    Rob's15adventure began on September 19th, and will end on October 19th. Three days in, he has already put on about 8 pounds, just a little bit16the trash that the average American produces in that time. But 30 days later, he will have put on over 130 pounds of trash. If you're wondering17on Earth he's going to carry all that garbage around, you should know that he will be wearing a custom-made trash suit to18around 135 pounds of trash. Still, that's19his own body weight, so it's not going to be20to move around.

    There may be a 1 between later bedtimes and weight gain, new research suggests.

    Researchers studied 3, 342 adolescents starting in 1996, 2 them through 2009. At three points over the years, all reported their 3 bedtimes, as well as information on fast food consumption, exercise and television 4. The scientists 5 Body Mass Index at each interview.

    After Controlling for age, sex, race, ethnicity and socioeconomic 6, the researchers found that each hour 7 bedtime during the school or workweek was 8 with about a two-point increase in B.M.I. The effect was 9 even among people 10 got a full eight hours of sleep, and neither TV time nor exercise 11 the effect. But fast food consumption 12.

    The study, in the October issue of Sleep, 13 questions, said the lead author, Lauren D. Asamow, a graduate student at the University of California, Berkeley. "14 what is driving this relationship?" she said "Is it metabolic changes that happen when you 15 late? And second, if we change sleep patterns, can we change eating 16 and the course of weight change?

    The scientists 17 that their study had limitations. Their sleep data 18 on self-reports and they did not have 19 diet information. Also, they had no data on waist circumference, 20, unlike B.M.I. can help distinguish between lean muscle and abdominal fat.

I came across an image recently of a distance runner with a message that told readers to persevere (坚持) at all costs. It reminded me of a conversation I had. My colleague's teaching assistant was asking for my advice. He wanted to know when to quit something. He described how he'd been playing an online game with people for some time. It hadn't been very fun lately, but there was always that small chance of a reward (upgraded equipment, etc). 

I inquired further about his relationship with the players and his gains from the game. I then discussed the sunk cost dilemma, a concept I studied in advanced school due to its personal impact. In high school, I applied to five universities, planning to choose the cheapest one. SUU offered the best scholarship, and after paying a $100 commitment fee, I heard back from another school with an even better scholarship. Despite the new offer, I stayed committed to SUU, believing that switching schools, even if it meant acknowledging the "wasted" $ 100, would have been the wiser financial choice. 

A rational (理性的) decision maker is not ruled by past investments, but weighs future outcomes. I didn't focus on future outcomes when weighing colleges. I focused on the money I sunk into SUU. Rather than evaluating future career options, I focused on the fact that I'd already taken elementary education courses. 

I'm not the only one that's fallen prey to this. I wear clothes I dislike simply because I spent money on them (and that money won't come back). Unhealthy relationships last because of the invested time (leading to more unhappy years). However, time, effort, or money that you've invested doesn't mean you should continue. Society often stresses perseverance — never quit, never give up, don't waste. However, only you know your right path. Walking away can be the toughest choice. You might realize a path you're on is no longer the right one or never was.

It was a terrible day. Snow had been falling all day long, making the trip risky. I would rather have been in my 1 home than drive along on such a cold day, but I didn't have a choice. I had to have my paper work handed in and then pick up my son.

The snow 2 to fall as we drove along for the 15-mile trip back home. I slowed the car and glanced (瞥) at my son in his heavy coat as he looked 3 out of the window with a blank expression. In the eyes of the world he was looked upon as a mentally disabled child.

4 , over the years what I saw was a beautiful, 5 and merciful (仁慈的) soul. He had shown me more about love than I could have ever 6 on my own.

I 7 the car even more as we approached a sharp curve (曲线) . As we rounded it I saw a shivering (颤抖的) young woman in a light jacket walking in the snow storm. I 8 and let her in. She was heading for her mum's house to visit her son whom she hadn't seen for months. She had experienced a lot of 9 and tragedies (悲剧) . Yet, she still held out hope for a new job and tried to 10 a new life for her son and herself.

I took her as far as I was able to and dropped her off. She 11 me for the lift and I told her I wished I could have done more to help. Then as we were about to leave, my sweet son took off his coat, 12 down the window and gave it to her. She put it on, 13 and waved to us as we pulled out on the road.

In this world we will face many problems and 14 . Sometimes it seems that our entire lives are a trip down a curvy and dangerous road. Yet the power of 15 takes us straight back to a broad smooth highway.