他们履行合同后,我才付款.用英语怎么说？

他们履行合同后,我才付款.

I withheld payment until they had fulfilled the contract.

withheld

withhold过去式及过去分词；

例句
A fundamental human right is being withheld from these people...
这些人被剥夺了一项最基本的人权。

payment

n. 付款，支付，报酬，报答，偿还，惩罚，报应；

例句
These returns will not be enough to meet the payment of annual bonuses to policyholders.
这些收益不够支付投保人每年分得的红利。

until

prep. 到…为止，在…以前；conj. 到…为止，在…以前，直到…才；

例句
The threat is likely to remain in abeyance until next year's meeting in Reykjavik.
这一威胁很可能会一直存在下去，直至明年的雷克雅未克会议。

they

pron. 他/她/它们，人们，大家，政府，当局，她们；

例句
The storms had abated by the time they rounded Cape Horn.
他们绕过合恩角时，暴风雨已经减弱。

had

v. 有（ have的过去式和过去分词 ），（亲属关系中）接受，拿，买到；

例句
He claimed that his parents had abandoned him...
他声称父母遗弃了他。

fulfilled

adj. 满足的，个人志向得以实现的；v. 满足( fulfil的过去式和过去分词 )，执行，尽到，应

例句
The company has not fulfilled certain contractual obligations...
该公司没有履行合同规定的某些义务。

the

art. 指已提到的人（物），指说话人与听者已知的人（物），用于独一无二的事物前，与形容词最高级和序数词连用；

例句
He did have a real knowledge of the country...
他对该国的确知之甚多。

contract

n. 合同，契约，协议；

例句
The House of Lords affirmed that the terms of a contract cannot be rewritten retrospectively.
上议院申明合同条款改写后不具备追溯效力。