按要求改写句子。

1. You had a good trip last Sunday. (变成一般疑问句)

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2. He hurts his hand. (变成一般过去时)

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3. I am playing football. (变成过去进行时)

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4. The old man fell at the station. (变成一般现在时)

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5. He went to Beijing by train. (就画线部分提问)

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临床以测血清钾为准，影响血钾测定结果的因素不包括

A．血清标本冰冻保存后使测定结果下降

B．血浆钾比血清钾低0.1～0.7mmol/L

C．全血未及时分离或冷藏均使结果升高

D．标本严格防止溶血

E．采血前患者肌活动可使结果升高