Next Sunday is Thanksgiving Day.Have you got any idea _____ we celebrate it?
The doctor will see you again next week. _____, you must rest as much as possible.
Of all the books on the shelf, is of any use for improving our practical skills of survival in the competitive world.
—How was your recent trip to England?—I’ve never had ______ one before.
When you talk about a person’s _____, you are referring to the country, race, or social class of their parents or ancestors.
In ____ accident _____ knowledge of first aid can make _____ real difference.