I should say ‘by,’ not ‘of,’ in the given sentence, shouldn’t I?

After the speech by Mr. Roberts, Mrs. Smith expressed her gratitude to the audience.


Who wrote and delivered the speech?

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teechrWho wrote and delivered the speech?

Mr. Roberts, teechr.

The original is fine as it is; use "by", not "of".

Thank you very much, teechr.

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