This paper focuses on four studies of pupils' reading comprehension completed at the University of Alberta. A number of investigators have described the acquisition and use of connectives by pupils and have indicated the importance of connectives in the development of abstract logical thinking. (Teachers often consider these words too simple to teach in reading classes except as sight words.) One of the author's concerns was the identification of connectives in three series of basal readers widely used in Canada at the upper elementary school level and an investigation of the understanding children have of them in reading. The amount of subordination produced by children eight to 12 years of age ranges from 10 to 30 percent of their total sentences with the amount increasing from year to year, but their basal readers use connectives in about 37 percent of the sentences and the amount is almost constant from grade to grade. (Forty two connectives were identified.) As important as this task of description and explanation of oral and written English language patterning may be to educators, the investigations cannot be restricted to language matters only but must encompass the interaction between reading and the logical development of pupils. (AMM)