搜题请搜索小程序“爱下问搜题”
问题 列举题

我国古代四大发明。

                                                                                                                                                            

                                                                                                                                                            

答案

造纸术；印刷术；指南针；火药。

问答题 简答题

哪些是电信设备维护应注意的事项？
查看答案
名词解释

亮氨酸拉链基元
查看答案