Rewrite the following sentences in conversational style. 1.I hereby acknowledge receipt of your July 7 letter. 2.Anticipating your reply by return mail,I remain. 3.We take pleasure in advising that Contract No.2017 is hereby canceled. 4.I shall appreciate the pleasure of your reply. 5.This is to advise that henceforth all invoices will be submitted in duplicate. 6.You are hereby advised to endorse the proposal and return same to the undersigned( 署名人 ) 。 7.In replying to your esteemed favor of July 7,I submit under separate cover the report you requested. 8.Replying to your letter of August 3 we should state that we deem it a great pleasure to accept your kind offer to serve on the committee.