Personally speaking, what I like most about Australia is the people themselves.

personally 是副词，来自形容词 personal（个人的），加上后缀 -ly 构成，意思是“就个人而言、亲自”。 speaking 是动词 speak 的现在分词形式，意思是“说话、发言”。 personally speaking 是一个固定短语，意思是“就我个人而言”，用来引出个人观点或看法。