A study designed to investigate to what extent ethno-linguistic background affects speech patterns and syntactic flexibility of grades one, four and six children from monolingual, bilingual-French and bilingual-German rural communities. A total of 216 randomly selected subjects were used; they were selected from nine rural Manitoba schools, and they were drawn in equal frequencies from grades one, four and six in each of the nine schools. The criterion measure for ability was Pintner Cunningham Primary Test for grade one, and the Pintner General Ability Test for grades four and six. All the language samples were segmented into minimal terminable units (T-units) single independent predications together with any subordinate clauses that may be grammatically related to it. The indices adopted for the study were differentiated on a dichotomous scale: positive and negative. Linguistic performance credited to the positive scale was assumed to indicate language maturity. Performance measured on the negative scale indicated deficiency in language development. Findings include: The only sentence-combining transformation categories favoring the grade six subjects were the Infinitive Phrase + Subject and the Coordinate transformations. Only two transformation categories showed any significant relationship to the sex variable; and the ability variable proved significant in all tested categories except Coordinate Structure transformations. (Author/CK)