—What are you busy ___?—I’m busy ___ a letter to my mother.
You’d better go there by train. The train ticket is _____ the plane ticket.
She brought with her three friends, none of _____ I had ever met before.
_______ ambassador who did his best to prevent the war is of _______ benefit to the place.
I will never forget those days, ______ I spent in the countryside together with my grandmother as a child.
─ How did you find the goods, Mrs. White?---- ______. They are well worth the money, I suppose.