SUMMARY
The aim of this study was to investigate the effect of using the gap task of opinion, reasoning and information on speaking skills at the secondary school level. This study used a quasi-experimental research method involving 352 students. The three experimental groups received treatment with gaps in opinion, reasoning, and information gap tasks. All groups were examined for their initial speaking ability. The experimental group was given an intervention with gaps in opinion, reasoning, and information while the control group was given a traditional intervention to improve speaking ability. After the intervention had been carried out, all groups were examined for their speaking ability. Data analysis was performed using one-way ANOVA. The results indicated that the experimental groups showed a significant increase in speaking ability compared to students in the control group in the post-test phase. Intervention from giving the gap task of opinion, reasoning, and information is more effective for improving speaking skills. Three assignments of opinion gaps, reasoning, and information can improve students' speaking fluency. Of the three assignments, the information gap assignment provides the most significant contribution compared to the gap of opinion and reasoning tasks because the instructions in the information gap task are more varied and more intensive in encouraging students to interact in various contexts. Based on these findings, the researcher recommends designing materials by creating assignments that contain gaps in opinions, reasoning, and information to achieve learning objectives.https://doi.org/10.26803/ijlter.22.2.7