willing

voluntary, willing

这两个形容词均有“自愿的”之意。
voluntary: 使用广泛，侧重不受约束，行动不为其他影响所左右。
willing: 着重自愿、令人愉快或急切地去行动。

名词 willing:

1. the act of making a choice
   同义词：volition

动词 will:

1. decree or ordain
   同义词：will
2. have in mind
   同义词：will, wish
3. determine by choice
   同义词：will
4. leave or give by will after one's death
   同义词：bequeath, will, leave

形容词 willing:

1. disposed or inclined toward
2. not brought about by coercion or force
   同义词：uncoerced, unforced

1. I don't know whether he is willing to come.
   我不知道他是否愿意来。
2. The spirit is willing but the flesh is weak.
   心有余而力不足。
3. I'd like to buy your house if you are willing to sell it.
   如果你愿意卖的话，我想买你的房子。
4. I wouldn't be willing.
   我不会愿意的。
5. She's the willing horse in the office and so gets given most of the work to do.
   她是办公室里埋头苦干的人，大部分的工作都交给她去做。
6. He is always a willing helper.
   他是一个乐于帮忙的人。
7. Are you willing to help?
   你愿意帮忙吗？

will.ing

adj.（形容词）
Disposed or inclined; prepared:
愿意的，乐意的，有…意向的：
例句：
I am willing to overlook your mistakes.
我愿意忽略你的错误

Acting or ready to act gladly; eagerly compliant:
乐意的，心甘情愿的：愉快地做的；积极肯干的，非常配合的：
例句：
.The spirit indeed is willing, but the flesh is weak.(Matthew 2':4)
.精神上乐意接受的，但肉体上却很虚弱.(马太福音2':4)

Done, given, accepted, or borne voluntarily or ungrudgingly.See Synonyms at voluntary
自愿的：自愿地或毫不吝惜地做的、给的、接受的或忍受的参见 voluntary
Of or relating to exercise of the will; volitional.
意志力的：与行使意志力有关的；由于意志的

【引伸】
will.ingly
adv.（副词）
will.ingness
n.（名词）