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Is the following sentence correct? If not why?

Much as I enjoy his jokes, she has never seen him.
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It should be....
As much as I enjoy his jokes....

Look as this sentence which is similar.
As much as she enjoys his jokes, she has never seen him in person.
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I am not a native speaker, Maj but AFAIK 'as much as' is used to say that two people or things are equal in some ways. 'much as' on the other hand, is an idiom meaning 'although' and it is not a short form of 'as much as'.
e.g. Much as I would like to stay, I really must go home.
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Comments  
orpheus, i beg to differ on you last point ... "as much as" means although. "much as" is casual speech interfering with the written language, and therefore, is NOT a real expression at all. (you are correct to state that "as much as" is an adverbial expression of equality.)
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