题干

甲、乙两列火车,以甲车为参照物,得出乙车向东运动的结论。若以地面为参照物,甲车的运动情况是()

A:一定向东运动

B:一定向西运动

C:一定静止不动

D:向东、向西运动或静止均有可能

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答案(点此获取答案解析)

D

同类题2

阅读理解

    If you like texting and are trying to lose weight, a new study found that using texting(发短信) to track diet and exercise habits may help you lose weight.

    Previous research has shown that keeping food and exercise diaries improves the likelihood of success when you are using it to lose weight. Using a computer or a pen and paper to record information, however, can be a burden and cause some people to give up.

    Duke University researchers said using text messages to track eating and exercise habits can save time, and increase the chances that people will stick with their weight-loss rules.

    The study included 26 obese/fat women with an average age of 38. The women used daily texting as part of their weight-loss program. The text messages focused on tracking personalized goals, such as avoiding sugary drinks or walking 10,000 steps a day. Messages also provided brief feedback (反馈) and tips.

    Every morning, the women received a text from an automated system that said, “Please text yesterday's personal information of steps you walked and how many sugary drinks you had.” Based on the women's responses to the text message, the system sent another text with personalized feedback and tips.

    After six months, the women who used daily texting lost an average of nearly 3 pounds, while another group of women who used traditional methods to keep food and exercise diaries gained an average of 2.5 pounds, according to the study, which was published in the Journal of Medical Internet Research.

    “Text messaging has become popular and may be an effective method to simplify tracking of diet and exercise behavior,” Dori Steinberg, who was responsible for this research, said.

    Steinberg said, “Text messaging offers several advantages compared to other self-monitoring methods. Unlike web-based diet and exercise diaries, data in a text message can be entered quickly on nearly all cell phone platforms so it is very convenient to receive feedback. Besides, because of the limited number of words used in text messages, it saves time.”

同类题4

请根据短文内容,回答下面问题,每题不超过8个词

Cell Phone Madness

    When I opened the box at my 12th birthday party, I couldn't believe my eyes. I had really got a cell phone!

    As soon as I got to my school the next morning, I showed off my phone and asked everyone for their number. It felt like I didn't even exist in that class anymore. I wouldn't pay much attention to the teachers because I was too busy on my phone. Luckily I didn't get caught using it. I was pretty sure that the teacher did notice that I stopped paying attention to her because a week later we took a test and I got Grade D for the first time. To make matters worse, my mom had to sign the test. It was hard to show my mom the paper. She never expected “D” on my tests. Well, finally, I showed her and she couldn't believe it. She was angry but most of all, she was disappointed(失望的).

    Weeks passed and my parents started to dislike the fact that I had a phone. They would say, “We have noticed that you never pay attention to us. It's like you have your own little world now and we don't communicate as much with your phone.” I acted like they were wrong, but then I started to wonder if it was true that I was spending too much time on the phone.

    A week later I tried going a whole day without a cell phone and it didn't go that badly. I had so much fun because I was actually spending time with my family and paying attention to them. From that day, I had a different point of view towards cell phones.

    Phones really take you away from the rest of the world.I'm not saying that phones are bad and not to use them, but you do have to spare some time to spend with your family and not get stuck with your phone all day. My phone took away time from my homework and from my family. It also affected my grades.

    I will keep using my phone, but I will have it under better control.