I don’t doubt ____________ she can do it well, but I doubt _________ she is willing to do it.
---Where’s Lucy? ---I’m not sure. She ________ in the school library.
Let’s ask Michael. I think he can _______ a good idea about how to deal with this problem.
The article is ________ more difficult than that one, so I think I can understand it with the help of a dictionary.
He failed in the English speech contest, ________ he did his best to prepare for it.
Could you please ________ such a thing again?