SARS ________ in Hong Kong in the winter of 2002 .

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When you come into the exhibition hall, you can see a large board with a notice on it, saying visitors ________ not to touch the exhibits.

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—Has William finished writing his graduation paper yet?

—I don't know exactly, but he ________ all day.

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—Would you like to tell me what our teacher said just now?

—She said that light ________ faster than sound.

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—Did you telephone the manager's office?

—Yes, he ________ back before 9 o'clock this morning.

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You can certainly leave the classroom as soon as your homework ________ .

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I should very much like to have gone to that party of theirs, but ________ .

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—Did you meet the pianist at the station?

—No, he ________ by the time I ________ there.

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Did you tell me that there ________ an English test the next week?

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—What else did you do this morning besides doing the shopping?

—Two hours ________ washing the windows and floor.

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