Điền từ ngữ với thì thích hợp vào chỗ chấm: 1. I ( not hear) ... from him since he ( dissapear)... 2. After all the guests ( leave ) ..., she (go)... back into the living room and (turn)... off all the lights 3. By the time you finished cooking they ( do)... their homework  4. This time yesterday they (sit)... in the train on their way to Paris  5. I came to class late when I (enter) the teacher (write) something on the board