---Have you ever been here before?---No. this is the first time that I to the Great Wall. A comes B have been C came D had been
Over_____ past thirty years, the old man has led _____ comfortable life.
________ he said at the meeting the other day was________ impossible.
—Her father is very rich. —________She wouldn’t accept his help if it were offered.
The living room is clean and tidy, with a dining table already ________ for a meal to be cooked.
Computers and mobile phones, though they are indeed making our life________ and more________, have reduced the need for face-to-face communications.