【题目】(2017·北京改编) A machine with a specific purpose has another quality, one that we usually associate with living things: a wish to _____________(保存) its own existence.
在线课程【答案】preserve
【解析】句意：有特殊用途的机器有另一种品质，一种我们通常与生物联系到一起的东西，即一种保存自己存在的愿望。“to ____ its own existence”是动词不定式作定语，修饰a wish，故该空填动词原形preserve。