Scientists are warning that ________ emissions of carbon (碳排放) are cut, we could be heading for an environmental disaster.
It was so dark that he ______.
It was foolish of him to ___ his notes during that important test, and as a result, he got punished.
The English spoken in the United States is only slightly different from____ spoken in England.
While shopping, people sometimes can’t help ____into buying something they don’t really need.
We’ve tried every _______ to solve the problem.