题目

—Mom, can I leave my homework for tomorrow?—I’m afraid not. Don’t _________ what you can do today till tomorrow.A．put onB．put downC．put upD．put off 答案：D解析: 略下列各组物质的晶体中，化学键类型相同、晶体类型都相同的是(      )A．CO2和SiO2B．C60和C(金刚石)C．NaCl和HClD．CO2和H2O