您好，in addition to和in addition都是很常见很常用的短语,都有“除了、还有”的意思,但它们的用法是完全不同的, In addition to整个词组相当于一个介词,所以to的后面要接宾语.例如:In addition to native plants,this garden contains numerous trees and flowers from overseas.除了当地的植物之外,这座花园还有无数来自海外的花草树木.In addition相当于副词,通常放在从句的句首,后面接完整的句子.例如：This garden has the best collection of native plants.In addition,it contains numerous trees and flowers from overseas.这座花园有当地植物的最佳珍藏.另外,它还有无数来自海外的花草树木.许多词可以和它替换,如：additionally,furthermore,besides.