1. 读句子, 猜谜语, 选择正确的答案写在横线上。

light   blackboard   window   classroom

1. （1） It's dark(黑暗的). You can see things clearly (清楚地) with it. It's a . 
3. （2） It's very cold. You should close the .
5. （3） It's black. Teachers can write on it. It's a .
7. （4） There are many desks and chairs in it. We have classes there. It's a .