Children's use of four semantic cases in tow conditions.

The production of agent + action + object + locative relations by 3;6- and 5;6-yr-old normal children and language-disordered children was investigated These utterances were produced after children observed object manipulation or while copying object manipulation. The results indicated a developmental trend in the use of case relations. The manipulation task enhanced the use of case relations by the language-disordered group, whereas the observation task was more effective (or equally effective) for the normal groups.