Receptive and expressive language difficulties are some of the core challenges facing children with Autism Spectrum Disorder (ASD). Emerging research suggests that for children with ASD receptive language is more impaired than expressive language. Specifically, abstract concepts like prepositions, are challenging for them. Aided augmented input has been shown to be an effective means of facilitating understanding in some children with ASD, however the amount of aided augmented input required to ensure effective understanding has not been determined. The aim of this study was to measure and compare the participants’ ability to follow instructions containing prepositions, under two conditions of aided augmented input. A with-in subject research design, involving 17 participants with ASD, was used to measure the accuracy of responses to instructions containing prepositions. Each participant was presented with 12 instructions. Half of the instructions were provided with 25% aided augmented input (prepositions only) referred to as Condition A, and the other half were presented with 75% aided augmented input (subject, preposition and location) referred to as Condition B. Their responses to the instructions were recorded and analyzed. Results suggest that there was no statistical difference between the two conditions of aided augmented input. Eight participants responded better under Condition A and five participants responded better under Condition B. Four participants responded equally under both conditions. The findings suggest that some participants may benefit from more aided augmented input and some from less aided augmented input. There is need for additional studies to determine the conditions of aided augmented input needed for the effective understanding of instructions containing prepositions and factors affecting the outcome. / Mini Dissertation (MA)--University of Pretoria, 2019. / Centre for Augmentative and Alternative Communication (CAAC) / MA / Unrestricted