In the past half-century, average incomes _______ quickly in developed countries, yet happiness levels have remained almost the same.
On the top of the hill ______.
Although the machine is _______, you need to use it correctly and safely.
—Could I use your dictionary? —Yes, ______.
—Sorry indeed. I______ to your birthday party if … —Forget it. I know you were out on business.
Recently a debate about ______is real beauty has been raised. People are pushed to think some questions like ______ is better,artificial beauty or natural one.