It's a picture of the Great Wall 对划线部分提问
问题描述：
It's a picture of the Great Wall 对划线部分提问
答
It's a picture of the Great Wall.
意思是：这是一幅长城的图片。
答
对 “ a picture of the Great Wall" 提问：What's it?
对 the Great Wall 提问：What's the picture of?
答
What's the picture?
答
它是一幅长城