Hardly had he entered the room than all the lights went out27/64Circle the letter A, B, C, or D to show the underlined part that needs correction in each of the following questions Hardly had he entered (A) the room than (B) all the lights (C) went (D) out.had he enteredthanthe lightswentGiải thíchĐáp án B Cấu trúc: hardly…when…:ngay khi…thì… Nên phải sửa “than”-> “when”.