题干

某同学在做“制作洋葱表皮临时装片”实验时进行了如下操作:

    ①撕取一小块洋葱鳞片内表皮;

    ②在载玻片上加一滴清水;

    ③盖上盖玻片;

    ④将洋葱表皮放入水滴中;

    ⑤用碘酒染色。

    以上操作的正确顺序是____

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②①④③⑤

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Why I've taken a break from holidays

    It is now close to four years since I last took a holiday. This is because I have come to the conclusion, over the course of my adult life, that I am not very good at it. You might think this sounds like saying you're not very good at drinking tea or listening to music. What could possibly be difficult about the natural act of putting your working life on hold for a couple of weeks and going somewhere warm to do nothing?

    I was a model holidaymaker as a kid. However, the problems started during my twenties. A trip to the south of France was ended after just two days, mainly because I had an urge to check my e-mails. Similarly, my honeymoon was cut short by 48 hours—not because my wife and I weren't enjoying ourselves, but because we were missing our cats.

    So what is my problem? On the surface, I'm probably a bit of a homebody. And I just find the pressure of being on holiday too severe: it always feels like having a gun held to my head and being forced to have fun. Somehow, packing a list of possessions and meeting a scheduled flight has none of the excitement of suddenly deciding to take a day off and driving somewhere for the fun of it.

    Thankfully, I'm not alone. This summer, most of my friends have decided not to have a break. And a recent survey (调查) proved the downside of holidays, with the results showing that nearly two thirds of people found that the calming effects of a holiday wore off within 24 hours, as stress levels returned to normal. And this year The Idler magazine published its Book of Awful Holidays. Here you will find a list of the five most ecologically-damaging vacations it's possible to take, along with 50 painful holiday experiences voted for on The Idler website.

    What interests me is what the concept of a “holiday” says about our lives. For me, the point of living is to have a life you enjoy for 52 weeks a year. The more I like my life and the better I structure it, the less I want to go away. Maybe I'm an unusual person for not liking holidays, but I just feel the time when I'm not working is too valuable to waste on them.