When communicating with business associates whose native language is different from your own, no matter how proficient you think you are in their language or they in yours, it's a good idea to double-check if anything is less than absolutely clear. A foreign business contact recently wrote to say he'd be in town briefly "by Wednesday" and wanted to meet. We set an appointment which I duly entered in my calendar. Only when it was too late did I discover that he was only in town until Wednesday and had intended to meet on Tuesday. Another lesson learned the hard way.