For his outstanding sales performance, the company upgraded him to regional manager.

upgraded 是动词 upgrade 的过去式。upgrade 由前缀 up-（表示"向上"）和 grade（等级）组成，字面意思是"提升等级"，引申为"晋升职位"或"提高级别"。 在句中表示公司将他提升到更高的职位等级，即从原来的职位晋升为区域经理。