题干
Look, the lights in the room don’t . Someone must forget .
A：put out; going them out
B：be out; put them out
C：go out; to put them out
D：go out; putting them out
答案(点此获取答案解析）
C
Ho可有效地治疗肝癌．该同位素原子核内中子数与质子数之差为（ ）