They may be asked to accept or decline the offer by a certain date, and perhaps to make a deposit (which is usually nonrefundable).

学校也可能提出，学生可以在某一日期内接受或拒绝该校的录取，或要学生付保证金(通常是不退还的)。

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All course fees are nonrefundable and must be paid in advance of a student commencing school.

所有学费都必须在开课之前支付，支付后无退款。

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In the new law, Congress requires that a taxpayer submitting an offer make a nonrefundable 20% deposit of what he proposes to pay.

FORBES: When Congress hunts for revenue, anything goes.

As Mr. Hartwig suggests, trip-cancellation coverage is best for travelers who are spending a lot of money for a nonrefundable itinerary, such as a cruise or a journey involving multiple flights or modes of transportation.

WSJ: Is Travel Insurance Worth the Cost?

Similarly, if the amount showing as tax due on your federal form 1040 at line 46 (or form 1040A, line 28) is less than the credit, the credit must be reduced since this is a nonrefundable credit.

FORBES: Ask the taxgirl: Child Tax Credit