题目内容
10．Though there are many difficulties，we will never give up until we find out what happened to the sunk ship of Korea．（改写句子，句意不变）Though there are many difficulties，we will never give up if the truth of the sunk ship of Koreaisn'tfound out．
分析 虽然有很多困难，我们不会放弃直到我们找到韩国沉船到底发生了什么．
虽然有很多困难，如果韩国沉船的真相没有查清楚我们不会放弃．
解答 答案：isn't found．原句中的find out表示查明，弄清楚，下文中的主语是the truth of the sunk ship of Korea是find out的承受者，构成被动关系，再者下文是if引导的条件状语从句，遵循主将从现的规则，故用一般现在时的被动语态am/is/are+过去分词，主语是单数，故is，find的过去分词found，根据句意，这里应该是说如果真相没被查清楚我们不会放弃，故用否定，在is后加上not，故答案是isn't found．
点评 一般现在时的被动语态am/is/are+过去分词的呈现，各种类型的被动语态的构成要理解掌握．
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