Rohmah, Nuzulur, 2022, The Effectiveness of Task-Based Language Teaching on Students’ Grammar Mastery Across Different Levels of Critical Thinking. Thesis. School of Graduate Program State Islamic Institute of Kediri. Advisor: (I) Dr. Ary Setya Budhi Ningrum, M.Pd., (II) Nur Afifi, S.Pd, M. App. Ling, PhD. Keyword: Task-Based Language Teaching (TBLT), Critical Thinking, Grammar Mastery.The purpose of this study is to gather empirical information concerning the impact of Task-Based Language Teaching (TBLT) on students’ grammar mastery with different levels of critical thinking at Happy English Course 1 Pare-Kediri. The goal of this quasi-experimental study is to see if Task-Based Language Teaching students’ grammar mastery with different levels of critical thinking. The participants of this study were taken from students of Happy English Course 1 Pare-Kediri. Forty students were involved to be the object of the research where they were divided into two classes namely experimental class with 20 students and control class with 20 students.Data for Grammar Mastery was gathered through a grammar test. It involved twenty five multiple choice questions. Meanwhile, the ‘Watson and Glaser Critical Thinking Test’ was used to collect data on critical thinking. The following are the finding of this study: (1) There was a difference on students’ grammar mastery between students who were taught by TBLT and those who were not; (2) There was no difference on students’ grammar mastery between students who had high critical thinking and those who had low critical thinking; (3) There was no interactional effect between TBLT on students’ grammar mastery with different levels of critical thinking.

Rohmah , Nuzulur .   (2023). The Effective of Using Task-Based Language Teaching on Students Grammar Mastery Across Different Levels of Critical Thinking. IAIN Kediri