When the father came home, the naughty boy pretended ________ his homework.

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－What is behind that tree?

－There must be a dog ________ beside it.

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－Whose T-shirt is this?

－It ________ be John's. It's too big for him.

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I'll have a test ________ writing next week.

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－What do you think “upset” mean?

－I'm not sure. It ________ mean sad.

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－Did you go out for a picnic?

－No, we didn't go ________ the bad weather.

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－Mum, where is my pen?

－Oh, you ________ it in your grandmother's yesterday.

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－I can't get anything on the TV.

－There ________ something wrong with it.

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－Why is she worried?

－She's worried ________ her test.

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Mr. Smith ________ at home because the light is on in the room.

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