While we will certainly do our best to expedite the shipment,we

While we will certainly do our best to expedite the shipment,we find it impossible to advance theshipment _________ of schedule.
【正确答案】：ahead
【题目解析】：[解析]句意:尽管我们会尽力加快运输,但是我们发现根本无法在规定日期内提前到达。ahead of表示 “在之前”。