Reports whether or not second and fourth graders comprehend material written with frequent oral language patterns better than material written with infrequent patterns. Two reading comprehension tests were devised and given to all subjects, who comprised second and fourth graders in two similar schools; 163 second graders and 137 fourth graders were used. Test A used patterns that appear frequently in second and fourth graders' oral language (e.g., noun-verb-object), and Test B used patterns that appear infrequently in the oral language of the same grades; patterns were from Strickland's study (1962). Reading comprehension was measured by the ability to read a sentence and select one of three similar pictures that best represented the sentence content. Vocabulary, content, and grammatical complexity were carefully controlled across tests. Chi square analysis was used to determine differential effects of diverse language patterns on reading comprehension; t-tests were used to test mean score differences between grades and sexes. Results indicated that 1] significantly more second and fourth graders obtained higher scores on Test A than Test B (p