Sentences such as ‘Mary began the book’ are called indeterminate because they do not make explicit what the subject began doing with the object. These sentences represent a case study for a central issue: compositionality. There are at least two proposals for how the meaning of an indeterminate sentence is attained. One assumes some form of local semantic enrichment relying on internal analyses of the noun complement to yield an enriched composition ([begin the book] -> [begin reading the book]). Another view assumes classical compositionality, with much of the sentence interpretation being the product of pragmatic inferences triggered by a syntactic gap ([began [v [the book]]). The only study investigating this phenomenon in aphasia supported semantic coercion based on greater difficulty by Wernicke’s patients in understanding indeterminate sentences. We investigated the phenomenon in 41 healthy controls, and 14 individuals with aphasia from different etiologies, with lesions in the left- or right-hemisphere. Participants heard a sentence, immediately followed by two pictures. Their task was to choose which picture best represented the sentence they heard. Sentences were: (a) indeterminate (The academic began the research), (b) fully determinate (“preferred”: …conducted the research), (c) metaphorical (…dumped the research) or (d) determined but non-preferred (…abandoned the research). Non-fluent [NF] aphasics performed worse with indeterminate sentences, compared to controls. Also, individuals with RH lesions performed worse with indeterminate sentences than controls. Together, the difficulty shown by the NF group in selecting the correct picture when presented with an indeterminate sentence suggests that they have problems computing the syntactic gap that may serve to trigger a search for an appropriate event during semantic composition.