化油器的壳体有裂纹，修理方法（）。
A.可用气焊修复
B.可用烙铁修复
C.可用堆焊修复
D.可用熔焊修复
参考答案：B
— Look! Somebody _____the sofa.
— Well, it wasn't me. I didn't do it.
A．is cleaning
B．was cleaning
C．has cleaned
D．had cleaned
