The aim of this study is to make clear the significance of inferences in high school English reading classes. The kinds of inference are mainly divided into these two. (1) bridging inferences (2) elaborative inferences. (1) are inferences with which one grasps text information correctly and reads the text consistently. (2) are inferences with which one reads a text more deeply and elaboratively. One does not necessarily use elaborative inferences. In many English classes, teachers tend to focus only on bridging inferences. Therefore, the effect of using elaborative inferences is examined in this study.