As a representative of indefinite frequency adverb in modern English, “always” demonstrates a kind of objectivity. However, when traced back to the seventeenth century, “always” expresses an evidential subjective meaning. Based on the collected data from the seventeenth century to the twentieth century, this paper tries to explore the subjectivity evolution of “always” from the dimension of collocation between “always” and three other elements which include personal pronouns, epistemic verbs and negative particles. It is found that from seventeenth century to twentieth century, “always” not only has a tendency of objectification but also has a tendency of categorization. These findings is helpful to reunderstand the subjectivity and evolution of English language, especially the frequency adverbs.