题目

When she finishes ____the stories, I always enjoy ____them. A. writing; to read                            B. to write; reading C. writing; reading                           D. to write; to read 答案：C请从下列物质中选择适当的物质填空：A．硝酸铵　　　　B．氢气　　 C．天然气　　 D．生石灰（1）被称为最理想的“绿色能源”是______（2）“西气东输”的“气”是______（3）可作为食品干燥剂的是______（4）易溶于水，且使溶液温度明显降低的是______．