The boy made rapid progress. It surprised everybody. (So.....that....)

16. The boy made rapid progress. It surprised everybody.(So.....that....)
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17. He had a difficult exercise. He couldn't do it.(So.....that....)
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18. The speaker gave a long talk. Most of the audience felt sleepy.(So.....that....)
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19. We watched an exciting competition. We didn't want to go home.(So.....that....)
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20. It was an excellent show. We all enjoyed it.(So.....that....)
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