动作上的夸张处理一般用来强调动作的突然性。

Exaggeration is used to accent an action.

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与现在完成时相比，它强调动作继续进行或刚刚结束。

My daughter has been working here for five years and will continue doing so.

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昨晚玛丽一直在给妈妈写信。(强调动作情景，不一定写完信)。

Last night Mary was writing a letter to her mother.

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昨晚玛丽一直在给妈妈写信。(强调动作情景，不一定写完信)。

Last night Mary was writing a letter to her mother.

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