In the meanwhile, the quality of facial tissues was constantly improving, because more manufacturers went into the business of making tissues, and each manufacturer strove to make his product better than his competitors’.

【参考答案】

与此同时，面巾纸的质量也稳定上升，因为更多的生产商投入到生产面巾纸的行业中，每个生产商都努力使他的产品优于其竞争对手。