This study investigates when and how middle school students comprehend 10 basic grammatical terms such as subject, verb, tense, person, etc. The research questions are (1) When were the students able to comprehend the terms?; (2) Which was more helpful between their English class at school and their private tutoring or reference books for comprehending the terms?; and (3) what ways of teaching were considered effective/ineffective by the students for learning the terms? A survey was conducted on a total of 702 3rd-year students enrolled in seven middle schools in Gyeonggi, Gangwon, Chungbuk, and Gwangju, and among them 367 students that stated they comprehended the 10 grammatical terms presented in the survey were selected as the subjects. Their responses were analyzed through SAS to compute both basic descriptive and inferential statistics. Some of the important findings are (1) 40.87% of the subjects comprehended the terms during their 1st year at middle school, while 34.87% did while in elementary school; (2) for 51.23% of the subjects their private tutoring (reference book included) was more helpful than their English class for comprehending the terms; for 37.33% both were equally helpful; and for 11.45%, their English class was more helpful; (3) most subjects considered all of the nine ways of teaching presented in the survey to be effective.