--What was Wang Tao doing at that time?

题目

--What was Wang Tao doing at that time?
--I"m sure he must have been playing the piano.
为什么这里用must have been playing,不是完成进行时吗?说明现在还在做唠?
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As we now know,nowhere else in the world can there be such a quiet and beautiful.
我搞不懂这句话为什么there放在can和be中间?它作什么成分?
如果不倒装应该是什么样子的?

答案

1.must have been doing sth并不是什么现在完成时,而是对过去某时间正在发生/进行的动作的语气非常肯定的推测,可以翻译成“当时肯定正在做某事”.
2.这是英语中常用的部分倒装.
1）其规定如下：如果把句子的否定词或含否定词的短语（一般是状语）提前至句首的话,则该句必须采用部分倒装结构,其变化类似于变一般疑问句一样,即把该句的be动词/助动词/情态动词也提前.
2）该句是一个含有情态动词can的there be句型,其原本句子为：
As we now know,there can be such a quiet and beautiful (place) nowhere else in the world.
楼主应该是少打了一个单词place.
翻译：就像我们现在所知道的那样,在世界上其他任何地方都没有这么一个安静而美丽（之处）.