will
Will, will Will will Will Will's will?
The sentence is a tongue-twister addressing one Will about whether a second Will intends to bequeath a third Will's testament document to a fourth Will, using 'will' as a modal verb, a verb, a name, and a noun all together.

Meanings (pronounced /wɪl/)
expressing the future tense or volition
- The meeting will start at noon.
- I will help you tomorrow.
to desire or intend; or, to bequeath in a legal will
- She willed her estate to her daughter.
- He willed himself to keep going.
a legal document expressing a person's wishes for the disposition of property after death
- The will was contested by the disinherited brother.
- She drafted a new will after her divorce.
a male given name, short for William
- Will took the bus to work.
- Cousin Will is coming for dinner.
Word origin
From Old English willan ('to wish, desire'), from Proto-Germanic *wiljaną, from Proto-Indo-European *wel- ('to wish, want'). The same root produces Latin velle ('to want', whence 'volition'), German wollen, and Russian volya ('will'). The proper name 'Will' is a short form of 'William' (Old English Wilhelm, 'desire-helmet'); the noun 'will' (testament) is a derivative of the verb meaning, since a will documents what you wish.
Fun fact
Four meanings of 'will' coexist: modal verb (future), main verb (to wish or bequeath), noun (legal testament), and proper name (short for William). All four descend from the same Proto-Indo-European root *wel- ('to wish'). The legal-document sense developed because a will literally documents what the deceased wished to happen with their property — a legal record of volition.