We investigate a relatively understudied phenomenon, the use of the (standard) past tense verb form as a (non-standard) past participle in English, as in I haven't drank in weeks and refer to this phenomenon as "past tense spreading". We explore this phenomenon in some familiar, large corpora of English, as well as utilizing the World Wide Web as a corpus through the Google search engine. The corpus-based approach allows us to examine details in the behaviors of many verbs across genres and to identify degrees of spreading among verbs. The web searches reveal differential behaviors for high-frequency and low-frequency verbs with respect to past tense spreading, an example, we claim, of Bybee's (2006) Conserving Effect. Past tense spreading also occurs more than expected with modal auxiliaries, a pattern which would not be predicted based solely on the nonstandard character of the phenomenon.