annul

他们决定废止这份合同，因为它违反了法律规定。

They decided to ___annul the contract as it violated legal regulations.

在欺诈证据曝光后，法官同意宣告这段婚姻无效。

The judge agreed to ___annul the marriage after evidence of fraud came to light.

市政官员着手废除这项过时的区划法规。

City officials moved to ___annul the outdated zoning regulation.