题干

根据如图所示的电路图,用笔画线代替导线,连接实物电路.

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解:由电路图可知,两灯泡并联,电流表测干路电流,开关S1控制干路,开关S2与灯L2串联,控制灯L2;从电源正极出发,先把开关S1、电流表、灯L2、开关S2串联起来,回到电源负极,然后把灯L1并联在灯L2与开关S2的串联电路两端,电路图如图所示.

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    As a child, I was always told to “eat my greens”. These were the unappealing vegetables that sat on the edge of my plate. Peas, and green beans, all looked and tasted 1. Let's face it, when there were so many other delicious treats to2 why eat boring vegetables?

    Since then my taste buds have3and I'm also fully aware of the health benefits of eating fresh vegetables. But we still need 4 of the amazing goodness these green super foods give us. In the UK, a campaign has been 5 for several years to encourage us to eat our “5 A Day”—five portions of fruit and vegetables. That's6 evidence has shown there are significant health 7 to getting at least five 80g portions of a variety of fruit and vegetables every day.

    But I struggle trying to fit these five portions into my daily 8 partly because I have a sweet 9 and vegetables are, well, tasteless. Researchers have been 10 how to make eating vegetables more 11. They analysed the psychology behind our food 12 and found that most of us are 13 by taste. Brad Turnwald from Stanford University says that “studies show that people 14 to think of healthier options as less tasty for some reason.”

    In Europe, a project called VeggieEAT has also been trying to find ways to get people to 15 more vegetables. Project leader, Professor Heather Hartwell believes in 16 encouraging people into eating the right things. One idea has been to put a 17 of a tasty looking fruit on a supermarket trolley as a 18 about buying something from the fruit store. She says, “Choice is a really 19 thing. But making vegetables look attractive will increase their sales.”

    Certainly, eating “twisted citrus-glazed carrots” does sound tempting, even if it just 20like a carrot, but if it makes us eat more vegetables then that can only be a good thing for our health.