CHỌN PH-ƠNG ÁN THÍCH HỢP ĐỂ HOÀN THÀNH CÂU SAU . I WAS LEARNING...
Câu 15 Chọn ph-ơng án thích hợp để hoàn thành câu sau .
I was learning maths when ...
A. my mother comes back
B. my mother came back
C. my mother has come back
D. my mother is coming back