A flat, folded paper container, especially for a letter.

信封扁平，装折叠纸的容器，尤其用来装信。

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You see I have to pay a deposit when I open a letter of credit. That will tie up my funds and add to the cost of my imports, especially for such a huge order.

你知道，开立信用证时是必须要交付押金的，这会占用我的资金，增加我的进口成本，尤其是这样一张大单子。

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Ask your supervisor and other managers you've worked with for a letter of recommendation. References, especially from high-level staff, carry a lot of weight.

请求你的主管或与你共事过的经理撰写一份求职推荐信。推荐信，尤其是高层管理人员的推荐信，在面试的时候会起到举足轻重的作用。

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