Mr Smith's lived in Guangzhou for many years, _________.

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He had nothing for breakfast this morning, _________?

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Doctors began to learn more about ________ made people sick.

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Now the population ________ ________ forty years.

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Nick had nothing for breakfast, ________?

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We _______ friends since the first day of primary school.

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please ________ your new dress to me.

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I often help him ________ the classroom.

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I like to hear the bird ________ in the morning.

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Do you know the answer ________ the question?

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