It is reported that China will not buy the Euro debt until some thorough research ______.
It was a time_______ the killer whales helped the whalers catch the baleen whales.
---Which one will I choose?---Well, you can take _______ of them; I’ll keep none.
---Don’t forget to bring my new books tomorrow afternoon. -- No, I ________.
We always keep ____ gas in case we run out.
With no one to ____in such a frightening place ,she felt helpless.