Our realty agent says the sales contract is valid.

我们的房地产代理人称该销售合同是有效的。

《柯林斯英汉双解大词典》

No modification of the Contract is valid unless agreed or evidenced in writing.

5除非书面约定或证明，任何对合同的修改都是无效的。

youdao

Absent precise language in a contract spelling out contingencies, courts use such doctrines as force majeure to decide whether the contract is still valid.

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U.S. citizens pursuing massage therapy for cruise lines also need a passport that is valid for at least three months after the end of the contract.

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The contract was not approved at the general meeting of MOR's shareholders and is therefore not legally valid, Viktorov insists.

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