I spent the whole day repairing the motorbike. The work was_____easy. A. nothing but B. something C. all except D. anything but 答案:D 解析: anything but 根本不对于可逆反应2SO2+O22SO3,在混合气体中充入一定量的18O2,足够长的时间后,18O原子 A.只存在于O2中 B.只存在于O2和SO3中 C. 只存在于O2和SO2中 D. 存在于O2、SO2和SO3中