24-month-olds are surprisingly good at understanding sentences, even when they cannot say any themselves and even when the verbs are ones which they have never encountered before. Some have argued that this implies that children are born with some kind of innate bias to map the agent (ie &'doer') of the action onto the first noun in a sentence. However, previous studies have not clarified whether successful comprehension by 2-year-olds is driven by a 'first noun = agent' bias or whether their comprehension is driven by other sentential cues. This project investigates this issue by measuring both eye-gaze and pointing preferences of 25-month-olds, 41-month-olds and adults to one of two video clips (eg girl acts on boy on one side of the screen and boy acts on girl on the other side of the screen) whilst listening to either active transitive sentences (such as 'the girl is glorping the boy') or passive sentences (such as 'the boy is being glorped by the girl'). If participants do show a 'first noun = agent' bias, they should prefer to look at the clip in which the first-mentioned noun is the agent, but only whilst they hear the initial part of the sentence.