—Mr. Hu, can you tell us how to learn swimming well?—Sure. But remember we can learn nothing well _______ hard work.
--- Must I finish my homework now?-- No, you ________. You can go home now.
Could you say it again? I can’t understand __________ you are talking about.
The man called his professor for help because he couldn’t solve the problem by _________.
I always tell my students _________ on the road because it’s really dangerous.
A: I enjoyed the performance very much.B: Yes, it was really good. I think ________ boy in white was the best actor.A: a B: an C: the D: /