EXERCISE 3I. CHỌN TỪ/ CỤM TỪ THÍCH HỢP (ỨNG VỚI A, B, C, D) ĐỂ HỊAN TH...

4. Bill didn’t go to school because of his illness.A. Because of Bill was ill, he didn’t go to school.B. Because Bill is ill, he doesn’t go to school.C. Because Bill was ill, he didn’t go to school.D. Bill didn’t go to school because he is ill.