Children's understanding of some temporal terms denoting order, duration, and simultaneity.

This study examined the comprehension by children of the concepts of order, duration, and simultaneity as reflected in certain linguistic structures. The children in the study were 3, 5, and 7 years old. Temporal order was examined through children's comprehension of two-clause sentences containing the conjunctions "after," "before," "since," and "until." Temporal duration was examined through children's understanding of one-clause sentences containing the progressive aspect and two-clause sentences containing the conjunctions "since" and "until." These two conjunctions signal duration in the main clause when they conjoin two clauses. Simultaneity was studied through children's comprehension of two-clause sentences containing "while." The results revealed that the order sentence structures ("before" and "after") were generally comprehended by the children before the duration or simultaneous sentence structures, although at 7 years of age children were still not performing above chance on the order relation in "since" and "until" sentences. The duration sentence structures were comprehended by the children before the simultaneous sentence structures. The results support the literature in cognitive psychology and in philosophy which argues that order is simpler than duration is simpler than simultaneity.