单句改错练习250题1, December is the twelve month of the year._2, You had better to stay at home on the rainy days._3, He discover the answer to the question, so the teacher smiled at him._4, John didnt have a good time, so did I. _5. I will do all what I can to protect the environment._6, There were some children wait for the bus at the bus stop. _7, Catherine married with Mr James three m