open macro

例句：

1. 1. The door is open;please come in.
   门开着，请进来。
2. 2. The curtains are open; let's see what's inside.
   窗帘开着，我们看看里面是什么。
3. 3. The window is open;it's a nice day outside.
   窗户开着，外面天气很好。