他是一个非常愿意的助手。

He is a very ___willing assistant.

它给了他们一个愿意的奴隶，即机器，它不知疲倦地工作。

It has given them a ___willing slave, the machine, which works tirelessly.

尽管有挑战，他仍然愿意承担这项困难的任务。

Despite the challenges, he remained ___willing to undertake the difficult task.