-- _____is that used for?---_____ the floor.
We drew this conclusion on the _______of research and experiments.
They are all interested in the newly-built apartments along the river, really want to buy them yet.
The chief editor expressed his doubt _______ senior people would enjoy reading such magazines.
— It is said that the famous cyclist_________ his parents is to visit our city next week.—I heard the news _________.
----Hello, may I speak to Jack?---- . May I take a message?