Bộ 3 Đề kiểm tra Unit 9 - Tiếng anh 10 iLearn Smart World có đáp án (Đề 1)

It was originally discovered in 1990 by a local man named Hồ Khanh while he (37)___________ for timber.

37/45

It was originally discovered in 1990 by a local man named Hồ Khanh while he (37)___________ for timber.

searched

was searching

had searched

had been searching

Giải thích

Chọn B