WHEN I CAME TO VISIT HIM LAST NIGHT, HE __________ HIS HOMEWORK. H...

46. - KIEM TRA 1TIET SO 1 TRON 4 DE
KIEM TRA 1TIET SO 1 TRON 4 DE
46. When I came to visit him last night, he __________ his homework. He said that he __________ it since 6 o'clock.A. did/did B. was doing/has been doingC. was doing/had been doing D. was doing/was doing