题目

Be careful! Wood is easy to         in such dry weather． A．set fire                                                       B．be set on fire    C．be caught fire                                             D．catch fire 答案：D下列化学用语既能表示一种元素，又能表示一个原子，还能表示一种物质的是(     )A．O B．CO C．N2 D．Zn