下列实验：①浓盐酸和二氧化锰混合加热制氯气；②无水醋酸钠和碱石灰混合加热制甲烷；③浓硫酸和乙醇混合加热制乙烯；④氯化铵和消石灰混合加热制氨气其中可用下图实验装置来制取的是____（填序号）．
下列实验：①浓盐酸和二氧化锰混合加热制氯气；②无水醋酸钠和碱石灰混合加热制甲烷；③浓硫酸和乙醇混合加热制乙烯；④氯化铵和消石灰混合加热制氨气其中可用下图实验装置来制取的是\_\_\_\_（填序号）．
用来
All that you said _____ true. All _____ reading their textbooks when the teacher entered.
All that you said \_\_\_\__ true. All \_\_\_\__ reading their textbooks when the teacher entered.
People use the 311 call system to report _____.
People use the 311 call system to report \_\_\_\__.
秒表上的长针是____针，短针是____针．表壳上的按钮是用来控制表的____及____、____的．
秒表上的长针是\_\_\_\_针，短针是\_\_\_\_针．表壳上的按钮是用来控制表的\_\_\_\_及\_\_\_\_、\_\_\_\_的．