23. Mum: Laura,  have you done the dishes yet?
    Laura: Well, I........doing them, but then I had to answer my phone
B. did start

phía sau là "had to" => phía trước QKĐ

did start=started: nhấn mạnh đã bắt đầu
24. ...........the film started when the phone rang
C. Barely had

Cấu trúc: Barely had +S+P2+when+S+QKĐ

25. Do you remember.........your bed when you were a child
D. making

Cấu trúc: remember+V_ing: nhớ gì đó đã xảy ra ở quá khứ

dùng cấu trúc này do câu có mệnh đề QK: when you were a child