句型转换。 1. Beijing is a big city. (变一般疑问句,并作否定回答) ____________ Beijing ____________ ____________ ____________? ____________, ____________ ____________. 2. What colour is it? (变复数句子) What colour ____________ ____________? 3. This is a map . (就画线部分提问) ____________ ____________ this?