Two groups of Czech children, 3-year-olds (N=28) and 5-year-olds (N=26), participated in a preferential looking experiment testing their comprehension of simple transitive sentences and their susceptibility to structural priming. Four temporarily ambiguous target sentences were presented, two with the canonical SVO word order, two with OVS word order, which is possible but marked in Czech. Each target sentence was preceded by an unambiguous prime sentence with SVO or OVS word order. In 3-year-olds, the presence of OVS primes reduced the garden-path effect observed in the OVS sentences. In 5-year olds, there were no significant effects of structural priming. In unambiguous prime sentences, 5-year olds showed the same level of comprehension in both the canonical and non-canonical sentences. The results suggest that 3-year-olds represent the abstract relationship between agent and patient roles and word order. Results from prime sentences suggest that 5-year-olds can interpret sentences with non-canonical word order.