Sentence: Having asked to speak at the convention, Dr Casagrande prepared some...

[Sophie]

I don't understand the meaning of this sentence. Please help me.

Having asked to speak at the convention, Dr Casagrande prepared some not.

Thank you very much.
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On earth there is nothing great but man, in man there is nothing great but mind.

[Mister Micawber]

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There is something wrong with it. 'Having been asked'? And 'prepared some not' is meaningless to me.
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Native English teacher at Mister Micawber's