Mr. White had no money for the taxi, so he had to ______ home.
---Let me help you to carry the box. ---No, thanks. I can do it by _______.
Don’t waste your time. You should ________ your work.
--- It’s good for you to ________ in class.--- I think so . Thank you.
You’ll be late _______ you leave at once.
--- Sixteen-year-olds should not be allowed to drive.--- _________ . It’s dangerous.