This work investigates the interface of language-mathematics, focusing on partitive and quotative division problem solving tasks. We investigate whether the difficulties students face when solving mathematical verbal problems can be related to linguistic complexity of the commands. We also discuss how the composition and linguistic structures that are used in the verbal problems can affect student s performance. We conducted three experiments with students of the second year of a primary school in Rio de Janeiro. In the first experiment, we used problems extracted from textbooks as experimental items; the results indicate a significant difference between the partitive and quotative conditions, resulting in a bigger number of correct answers regarding partitive division. In the second experiment, we created new commands, controlling their informational structure as well as their grammatical complexity. The results show a similar performance in both conditions. As for experiment 3, our aim was to investigate the type of interpretation students would prefer in ambiguous propositions, in which the subject of the sentence is a compound subject (coordinated structure). A preference for collective readings was observed. Also, when ambiguous structures are present, the performance of the students tends to vary depending on the conditions, declining on quotative division. Thus, the results of this research indicates that the difficulties students usually face in mathematical verbal problems can be reduced when the grammatical complexity is controlled - pointing towards the central role of linguistic variables in mathematical knowledge and in the elaboration of school materials.