This research is a classroom action consisting of two cycles with 32 students. Data collection methods used, namely the observation method and the test method. Observation method is used to get data about students' attitudes. The test method was used to determine the students' ability in studying the structure and language of persuasive speech teIX B ts by applying the inquiry method to class IX B students at State Junior High School 4 Marga in the 2020/2021 academic year after applying the inquiry method. This can be seen in the pre-cycle which is 31.25% with an average value of 63.04, the first cycle of students completes with a percentage of 62.50% with an average value of 68.75. The increase from cycle I to cycle II increased by 15.91%, in cycle II all students had completed (100%) with an average score of 80.86. The increase in the score is a sign that the ability to study the structure and language of persuasive speech teIX B ts for class IX B students of State Junior High School 4 Marga for the 2020/2021 academic year is getting better after applying the inquiry method. Based on the results of data analysis, it can be concluded that by applying the inquiry method students' abilities have increased. Thus, it is recommended for Indonesian language teachers to apply the inquiry method in learning activities because it has been proven that the application of the inquiry method can improve students' abilities.
