Entrenchment and preemption are theorized to constrain the novel use of well-attested constructions. This study tested the effects of these two mechanisms in second language (L2) learners’ acceptance of English denominal verbs (DVs). Two groups of Chinese English-L2 speakers (fourth-year English major students and teachers of English) judged the acceptability of English locatum (e.g., Lucy watered the rose) and location (e.g., Lisa boxed the apples) DVs. Results based on both corpus and introspective frequencies show that the fourth-year learners’ judgments on the acceptability of all DVs were significantly negatively influenced by the frequency of nominal forms of the DVs, suggesting that entrenchment constrains L2 learners from accepting English DVs. Results based on introspective frequency demonstrate that the teachers’ judgments on the acceptability of all DVs were significantly negatively affected by the frequency of alternative verbs, demonstrating that preemption has a role to play in restricting L2 learners’ acceptance of English DVs. Moreover, the obtained DV frequency based on both corpus and learners’ introspection is a significant factor that helps all the participants’ acceptance of the English DVs, suggesting that the more frequently a DV is used, the more likely L2 learners are to judge it as acceptable.