The problems, _____ properly, will seriously affect the relations of nations.
A. not solved B. if not solving C. if not solved D. if not to solve
The biggest problem was that thousands of travelers remained _____ outside because of the floods.
A. sticking B. stuck C. to be stuck D. to have stuck
We noticed that each animal and each tree in the park _____ being taken good care of.
A. are B. is C. were D. was
Part of the reason Charles Dickens loved his own novel, David Copperfield, was _____ it was rather closely modeled on his own life.
A. what B. that C. why D. whether
That is the only way we can imagine _____ the overuse of water in students’ bathrooms.
A. reducing B. to reduce C. reduced D. reduce
Don’t phone me between 7:00 and 8:00 in the evening. We _____ dinner then.
A. are having B. had C. would have D. will be having