Unless a check is signed, it is invalid.

支票除非签了名，否则是无效的。

youdao

Unless a check is signed, it is invalid.

护照过期是无效的。

youdao

If so, then it is invalid and a 406 is returned.

如果是，将为无效并返回值406。

youdao

That wasn't done here, and we believe, therefore, it is an invalid measure.

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It is hard to believe this bedridden invalid was once a national skiing champion.

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And while the pattern that supported this projection is now invalid, it will take a further correction and close below the 28.50 level before a new pattern of lower lows forces me consider the possibility of further, more significant declines.

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