参考范文(Word Count: 261)
When people think of inventions, they often think of things which are technically complicated, or which require electricity in order to work. This is especially true in the 21st century, with our obsession for mobile phones, portable computers, digital cameras and other electronic items.
However, many of the inventions which have changed our lives are very simple devices. Without the wheel, for example, we would not have cars, motorbikes or bicycles. Aeroplanes would not exist, as they would not be able to take off or land without wheels. Furthermore, wheels, in one form or another, are an important part of many smaller machines, like watches and computers.
Many other great inventions are even simpler. A wheel requires parts which move. This means that compared with a paper clip, an elastic band or a sheet of paper, it is quite complicated. But these smaller items are an essential part of every office. The same can be equated with pencils, sticky tape, and many other stationery items.
Great simple inventions can also be found outside the office, of course. In my opinion, some of the most important inventions are those which have a medical purpose, Aspirin and syringes, for example have helped to relieve pain and prevent or cure disease.
In conclusion, I believe that a great invention does not need to be complicated or technical. It can be something small or simple which has changed or improved our lives in some way. After all, most of us have a mobile phone, but it could not cure us if we became ill.