He ________ that he would help me, but he didn't keep his ________.

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--- I like the party so much, but I ________ go home. It's too late.

--- What a pity!

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--- Mr Li, may I go home now?

--- No, you ________. You should sweep the floor first.

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--- When shall we go to the park, this morning or this afternoon?

--- ________ is OK. I'm free the whole day.

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--- Look, the light in the teacher's office is still on. Mr Li is working there. He always works late at night.

--- It ________ be Mr Li. He has gone to London for a short visit.

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It's very interesting ________ the students ________ a picnic in spring.

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You ought to teach that boy ________.

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