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B

      Before windows were used, old h in Europe（欧洲）and Britain were very dark. Their great rooms were high w only one hole in the roof（屋顶）to let the smoke o from cooking fire. Later, people began to make the holes b to have more light and air in their homes. The first English window was j a small opening（口，孔）in the wall. It was cut long to let in as m light as possible, and narrow to keep out the bad w. However, with the window cut long, more wind than light would c in. This is why it was c “The wind's eye”. And the word “w” comes form two ancient（古代的）words for “wind” and “eye”