To make the extension required, set the value of the lower property to 1; to make it non-required, set it to 0.

要使扩展成为必须的，设置下面的属性值为 1; 要设置它为非必须的，设置值为0。

youdao

Coal reserves are due to be exhausted at the mine in around five years but an extension is required for the last three of those years.

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Therefore, an extension from the CFTC may be required.

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Handle the difficult Form 8949 reconciliations and explanations required on your tax return after the extension and before the final due date of Oct. 15.

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