Previous research has shown that verbs pose particular difficulties to toddlers as they refer to actions rather than objects, and actions are often different each time a child sees them.
To find out more about this area of child language, University psychologists asked a group of toddlers to watch one of two short videos.
They then examined whether watching a cartoon star repeat the same action, compared to a character performing three different actions, affected the children's understanding of verbs.
Developmental psychologist, Dr Katherine Twomey, said: "Knowledge of how children start to learn language is important to our understanding of how they progress throughout preschool and school years.
"This is the first study to indicate that showing toddlers similar but, importantly, not identical actions actually helped them understand what a verb refers to, instead of confusing them as you might expect."
Dr Jessica Horst from the University of Sussex who collaborated on the research added: "It is a crucial first step in understanding how what children see affects how they learn verbs and action categories, and provides the groundwork for future studies to examine in more detail exactly what kinds of variability affect how children learn words."
The research is published in the British Journal of Developmental Psychology by The British Psychological Society and Wiley.
Science Daily. 2014. “How toddlers learn verbs: New insight”. Science Daily. Posted: April 16, 2014. Available online: http://www.sciencedaily.com/releases/2014/04/140416101621.htm