This study was conducted to explore the ability of children (6 to 12 years of age) to understand certain relatively complex relationships as they are commonly signaled syntactically in our language. It was hypothesized that development in language performance during this age range was, in some measure, a function of a growing ability to comprehend the precise meaning of a variety of structural signals and to produce them in appropriate situations. Four such signals and the ability of 20 boys (ages 7, 9, and 11 years) to understand them were studied: (1) simple active-declarative utterances, (2) utterances involving complex logical relations, (3) special verb-indirect object relation utterances, and (4) utterances involving complex subject-verb-object relations. Little difficulty was experienced by any age group with simple statements, affirmative conditionals, and embedded sentences. Limiting contingencies with "although" and "but" and negative conditionals with "if" and "not" were more difficult, with performance improving with age. "Ask-tell" combination utterances and negative conditionals with "unless" were very difficult, especially for the 7- and 9-year-olds. Game instructions and a bibliography are included in the document. (WD)