Children are sensitive to syntactic structure when learning new verbs (Gleitman 1990). This has been shown in tracking transitivity (Naigles 1990), as well as in hypothesizing meanings for attitude verbs (Harrigan et al 2019). In English, desire and belief subcategories of attitude verbs have different finiteness properties; desire verbs occur with finite complements and belief verbs occur with non-finite complements. The current study explores adults’ sensitivity to varying distributions of finiteness in the complements of a novel attitude verb, aiming to better understand the mechanism for hypothesizing verb meaning based on syntactic distribution. We find that adults’ hypotheses for class of attitude verb are tied to the syntactic distribution—they strongly connect finiteness to belief verbs and non-finiteness to desire verbs.