An engagement to do or not to do something.

约定；诺言。

The thing to be done or left undone.

约定之事。

A cause or ground for hope or expectation of good in the future.

希望；有望。

To assure, or engage to do, something.

允诺；约定。

To give reason for hope or expectation.

有望；可望。

To engage or pledge (to do or not to do).

约定；允诺。

To agree to give, get, or the like, to or for someone.

答应(某人)某事或物。

To give reason to hope for or expect.

有...希望；有...期望。