提示：Alice得知Bill最近住院，问Bill发生了什么事。听说Bill房间失火，Alice感到遗憾。Bill说失火是由于熄灯后，John点燃了蜡烛，要继续阅读，但后来他却睡着了，随后，他的床着了火，他本人严重受伤，现在仍然住院。
Alice: Where have you been these days?
Bill: In the hospital.
Alice: In the hospital?{{U}} (51) {{/U}}?
Bill: Didn't you know that our room caught fire last Sunday evening?
Alice: Oh, really?{{U}} (52) {{/U}}. But what caused the fire?
Bill: Well, the light in our room was turned off at 10:30 as usual. John lit a candle{{U}} (53) {{/U}}. Unluckily he fell asleep with the candle still burning beside him.{{U}} (54) {{/U}}.
Alice: Oh, my God! How was John?
Bill: He was badly burnt{{U}} (55) {{/U}}.
Alice: Was he the only one burnt?
Bill: No. There were two more, including me.