A、Opening to look through. B、Light given. C、Wind. D、Wind’s eye. D

The first English window was just a narrow opening in the wall. It was cut long, so that it would let in as much light as possible, and narrow, to keep out the bad weather. However, the opening let in more wind than light. This is why it was called "the wind’s eye". The word window itself comes from two Old Norse words for wind and eye.
   Before windows were used, the ancient halls and castles of northern Europe and Britain were dark and smoky. Their great rooms were high, with only a hole in the roof to let out the smoke from torches and cooking fires.
   As time went on, people wanted more light and air in their homes. They made the wind’s eyes wide so as to admit air and light.
Questions 16 to 18 are based on the passage you have just heard.
16. What did the word "window" mean?
17. Why did the window get its name?
18. How did smoke go out in the ancient castles?