With a lot of difficult problems ________, the newly-elected president is having a hard time.

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--It ________ Jack who is at the gate of the library.

--It ________ him. I saw him off at the railway station just an hour ago.

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Children under 12 years old in that country ________ be under supervision when in a public library.

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Johnny, you ________ play with the knife; you 　　   hurt yourself.

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Jack ________ yet, otherwise he would have telephoned me.

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--John must have lost his way, for he hasn't arrived yet.

--No, he ________ his way. He has got a map with him.

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________ his life he believed that fighting and killing in wars were wrong. Which one is wrong?

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Some children were seen ________ in the garden all the morning. It must have been ________ who picked flowers.

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--I'm going to the post office.

--________ you are there, can you get me some stamps?

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Mother was worried because little Alice was ill, especially ________ Father was away in France.

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