This is nonrefundable, even if the source of the mineral is less prevalent than the lessee predicted it to be or if it is in an unextractable form.

即使矿源比承租人预测的要少，或者矿源是不可开采的形式，这也是不可退还的。

youdao

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。

youdao

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)。

youdao

For 2010 and 2011, many nonrefundable personal credits will be allowed against the AMT.

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Buyers typically sign nonrefundable contracts and put down deposits, paying the balance when the apartments are delivered.

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Tax expenditures include the inventory of Tax-Exempt Income, Adjustments to Income, Itemized Deductions, and Tax Credits (refundable and nonrefundable).

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