This report compared production of infinitival object complements during conversational language sampling to production on an elicitation task. Subjects included 25 children between the ages of 3;7 and 5;4. The children produced more two-noun infinitives and produced infinitives with more main verbs on the elicitation task. In the conversational samples, the children produced infinitives almost exclusively with early-appearing main verbs. These findings suggest that conversational language sampling may underestimate children's grammatical knowledge.