“This is what?”和“What is this?”到底哪个是“这是什么?”的意思?

what is it 和what is this的区别是什么? What is this?这是什么 what is this是什意思 what shape is this的意思 What is this?答语是什么? What is this?和What is that?的回答 为什么是What is this 而不是This is what? This is what I what What is this? this is what happens. What is this place? what is this?thank!