The U. S．declares it has the best medical technology in the world，but quite a lot of Americans have no ____to health care service．

Classification is a useful ______ to the organization of knowledge in any field.

I’m trying to break the _______ of getting up too late .

. Although I liked the appearance of the house, what really made me decide to buy it was the beautiful _______ from the window.

There is an obvious _________ between the cultures of the west and East.