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材料:两面同样大小的长方形镜子、胶布、闹钟等。做法: 把两面镜子(背面朝上)并排放在桌子上,将较长的一
Materials: Rectangular mirrors, tapes, alarm clocks and the like of the same size on both sides. Practice: put the two mirrors (back side up) side by side on the table, the longer one