--Susan, go and join your sister cleaning the yard.

--Why ________ ? John is sitting there doing nothing.

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________ it is to have a cold drink on such a hot day.

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I don't think ________ possible to master a foreign language without much memory work.

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I'm ________ I've seen somewhere before the boy ________we met just now.

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A big stone rolling from the hill hit him on ________ head.

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It's been many years ________ he worked here.

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--What have you ________ hydrogen, Mary?

--Balloons.

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Several weeks had gone by ________ I realized the painting was missing.

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I haven't seen you for a couple of days. What have you been up ________.

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He is so ________ a man, you can never praise him too highly.

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