—Where is he exactly?—I don’t know, but I saw him _______ an experiment in the lab when I passed by.
—This is ______room I told you before. --I see. Isn’t it _____ bright one?
By the end of last year, another new gymnasium________ in London.
Finally they came into a house,______ there were some flowers.
Great changes in every field _____ in the last ten years.
This article ______ in a hurry was not so good.