HOC24
Lớp học
Môn học
Chủ đề / Chương
Bài học
I was tired when you saw me because I ______ for the exam
A. studied
B. have been studying
C. had been studying
D. would study
At this time of the year the number of students in the university tends to ____.
A. dwindle
B. deteriorate
C. reduce
D. lessen