Toddlers can acquire verb meaning after hearing them only twice, according to a recent study.

Previous studies have shown that children as young as two years of age can successfully learn novel verbs after they've heard the verb many times while looking at a corresponding visual scene. However, researchers from Northwestern University found that the key to the toddlers' success is how the verb is "packaged."

They found that a 2-year-old toddler is more likely to learn the verb "waving" when a parent says, "A boy is waving a balloon," than if the parent had said "I see a boy, and a balloon. I see waving."

For the study, researchers looked into which of these ways of introducing novel verbs is most helpful to toddlers.

During these experiments, toddlers were introduced to six different novel verbs presented in one or two sentences of varying complexity. Some heard the verb in a single sentence that also included two nouns such as, "A boy is gonna pilk a balloon! Let's see!"

Others heard the verb in simpler constructions in which the familiar nouns were mentioned in one sentence and the new verb in another, such as "Let's see a boy and a balloon. Let's see pilking!" Then, both groups watched a short video clip of a boy waving a balloon.

Afterwards, the toddlers were shown two different pictures -- one with the same object, but a different action being performed on it (e.g., tapping the balloon), and one with the target action being performed on a new object (e.g., waving a rake). The toddlers were asked to point to "pilking."

Researchers said only the toddlers who heard the verb in the same sentence with both nouns (e.g., "The boy is waving a balloon") were able to successfully identify the target action.

"The results offer two insights," Sudha Arunachalam, lead author of the study, said in a statement. "First, by age two, toddlers have the remarkable ability to learn new verbs with very little exposure and apply them in novel contexts. Second, presenting the verbs in complete sentences supports the toddlers' abilities to do so."

Arunachalam added that these findings highlight the positive impact that rich communication can have on 2-year-olds' burgeoning linguistic abilities.