My mother is very nice. She is a ____ （work） in a clothes store. She usually gets up at 6: 30. Then she cooks breakfast for me. After ____（have） a bowl of porridge and some broccoli, she goes to work at 7: 30. There ____ （be）usually many people in her clothes store. So she is very busy.

    My mother's work in the morning is over at 11: 45, and starts again at 1: 30 in the afternoon. So she has to have lunch in the store. Her work in the afternoon ____ (end) at 5: 30, and she goes home at 6: 30. Then she has dinner with ____ (we）at home. After dinner we watch TV together.

在乙醛与氢氧化铜反应生成红色沉淀的实验中，关键操作是（　　）

根据材料回答问题。

材料一：陕变事起，曾……通电主张一致对外……不图讨伐令忽然而下，值兹强邻压境，国家民族，危在旦夕，方谋解救之不暇，何忍再为箕豆之煎，况汉卿（即张学良，字汉卿）通电各项主张，多位国人所同情者，屡陈不纳，迫以兵谏。绝不宜以叛逆目之。而政府逮加讨伐，宁不顾国人责以勇于对内，怯于对外？”

──1936年12月24日《桂林日报》

材料二：“大义当前，不容反顾，只求于救亡主张贯彻，有济于国家，为功为罪，一听国人之处置。”                    ──张学良、杨虎城通电全国的电文

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