网友jimzhen2021的解释是正确的
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额外说明一点,如果父母不能claim credit, 可以让孩子claim。有一个要求,父母不能claim child as dependent。如果孩子的收入不能provide half support, IRS said that parents CAN claim child as dependent. They never said that parents MUST claim child as dependent. 如同IRS规定中各种credit,standard deduction or itemized dedecution, you can take it and you don't have to take it. You can maximize your tax return or you can choose to contribute more to IRS revenue.