改进下列缺乏统一连贯性的句子：1)We are instal

题目描述

改进下列缺乏统一连贯性的句子：1)We are installing a centralized dictation system，and our current transcription production is days behind schedule.2)The keynote speaker will be Dr.Jay Cook，and vendors will display their products following the keynote address.3)We have placed a lien against your property and your payment is 60 days past due，which explains the lien.4)We are one of the nation’s largest office products distributors，and you can save 15 to 50 percent on your word processing supplies for your office which we supply to our 260 000 customers who are satisfied from coast to coast beeause we have been in business for the past twenty years satisfying our customers.