—Believe it or not, last month in America I came across the girl whose photo was in the drift bottle got three years ago .   —Really？That’s the most surprising          I’ve ever heard of！

I’ve listened to Professor Smith’s talk about medicine,but I still haven’t got a good understanding of its key _________.

I haven’t started writing my novel yet—I am still waiting for ______.

— The Coca-Cola company is one of the 　　　 of the match.— No wonder there are many Coca-Cola pictures around the sports field.

In the meantime, the question facing business is whether such research is ______ the costs.