She was about to go to bed when it suddenly to her that she hadn’t turned off the gas.A.

问题补充：

She was about to go to bed when it suddenly to her that she hadn’t turned off the gas.

A. happened

B. occurred

C. explained

D. referred

答案：

A. happened

(答案→)B. occurred

C. explained

D. referred

解析：考查动词辨析。句意“当她正要去睡觉时，她忽然想起来忘记关天然气了。”It happens that...“碰巧......”；It occurs to sb. that...“某人突然想起......”。故选B。