|Abstract:||The goal of this paper is twofold: (1) to review various behaviors of Class 1 suffixes with regard to stress assignment in English; and (2) to argue that the partial ordering theory -- a version of OT proposed by Anttila (2002), etc. -- properly accounts for such abundance among suffixes, predicting all and only the variation observed here. Each suffix turns out to be classified as having one of five stress patterns, all of which can be characterized by partial rankings of five general constraints. No other patterns than these five are predicted to arise because some of the constraint interactions do not produce any phonological consequence. A pilot survey on actual frequency of each pattern among suffixes is also conducted, and the result shows that the proportion of each pattern roughly corresponds to the proportion predicted by the present analysis, suggesting its appropriateness.