Forty-five children drawn equally from nursery school, kindergarten, and first grade were administered a nonverbal imitation task, a production task, a comprehension task, and a verbal imitation task. The results of the four tasks support the Temporal Complexity Hypothesis, which states that the components of temporality--order among events (O), simultaneity of events (S), and duration of events (D)--are acquired before their coordinations (OD, SD). Results also supported the order of acquisition hypothesis which predicted the order O, S, D. The order of difficulty of the tasks was found to be nonverbal imitation (easiest), verbal imitation, comprehension, and production. Within-subject analysis of the data supported cross-subject analysis. The following conclusions are drawn: (1) conceptual knowledge generally precedes linguistic knowledge; (2) children were able to imitate words just beyond their comprehension, suggesting that they may learn to use new words through imitation; and (3) children understand temporal words before they are able to describe temporal relationships. (JB)