单项选择题
A．at B．in C．on D．about
A. I think so. B. Don’t mention it. C. Please take it easy. D. What’s the matter E. And you F. I’d love to. G. But he panned to. H. Me, too.
A．Aluminum, silicon, and magnetic. B．Additive. C．Paving material. D．Cement.