I think ______ necessary ______ to take more exercise.
---Must we leave the classroom now?---No, you _____. You _____ leave after the bell rings.
---Can you tell me _____it is from home to school?---Sure. It’s about ten minutes’ ride.
---Could you please give the dictionary to Wang Feng?---Yes, of course! I’ll give it to him ________ he comes back.
---Would you mind ______ next to you? --- ____________.
---I don’t think Lily can sing _______ Lucy.---I disagree. I think Lily can sing ______ Lucy.