.—I think 20 dollars for it is OK.—No, I’d gladly pay _______ for it.
Many countries, for example, Mexico and Japan, _____a lot of earthquakes.
Each of the students, hoping to pass the exam, _____the book.
He told me the news_____, believe it or not, he had earned $1 000 in a single day.
The research is so designed that once _____ nothing can be done to change it.
If _____ carefully, the experiment will be successful.