-If we take a plane, we'll of course have arrived in Paris by the next weekend. (皖南八校)-Don't be sure, we should______the weather factor. What shall we do if it is foggy?
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.