It takes courage to stand up at work．Now more and more people are standing up when they are working on something important．Standing up is in fashion．Medical researchers have found that people who stand at work tend to be much healthier than those who sit．But I wasn't just looking for better health — standing would also improve how I work and relax my body． In recent years, many office supply companies have begun to sell adjustable desks．These so-called 'sit / stand' models are equipped with an electric motor that lets them shift from chair height to person height at the push of a button．Unfortunately, sit / stand desks tend to be expensive, hard to find and not very easy to test in person． I discovered that when I worked standing up, my mind was clearer and new ideas kept coming to me．I suspect that this is because when you're standing, you feel a bit unchained from your desk．If I got stuck on a word or sentence as I wrote it, I found myself shaking my arms, bouncing （跳） on my feet or stepping away from the desk for a bit — things I couldn't do in a chair．Often, standing up seemed to relax my mind enough for me to get over creative barriers． There's another thing about standing for a long time: I tend to get hungrier than I do when I sit on a chair．That feels like confirmation（证实） of the stand-up advocates’ belief that you burn more calories when you stand than when you sit．For this reason alone, I' m hoping that one day mass-market furniture companies can make many low-priced versions of sit / stand desks．We could all work with a bit more standing up． 小题1:The author likes standing up while working because __________． A．he wants to show that he has a lot of courage B．researchers say standing makes one healthier C．he intends to catch up the fashion trend D．he hopes to improve his work and relax himself 小题2:It can be inferred from the text that   ________． A．adjustable desks are mass-produced now B．adjustable desks are easy to operate C．cheaper adjustable desks will soon be available D．adjustable desks can be tried out easily 小题3:What is the main idea of the text? A．Standing up at work is a better choice． B．Standing up at work takes courage． C．Standing up at work burns more calories． D．Standing up at work will replace traditional sitting．