"Artists of all kinds have tried their best to express what love means to them."
Here's my take: "to express what love means to them" is an adverbial infinitive phrase.
1. You can move it around: To express what love means to them, artists of all kinds have tried their best.
2. It answers the question "why" or "in what manner" the verb happens. Artists of all kinds have tried their best. Why? "to express what love means to them."
Without that adverbial infinitive phrase, it's easier to see that the main sentence is transitive: THEY have tried SOMETHING.
"Their best" is a noun phrase/direct object. I don't have a problem with "best" functioning as a noun--contrast with "their happy" which clearly doesn't work.
To make the whole sentence passive would be clunky, but it is doable:
"To express what love means to them, their best has been tried (by artists of all kinds)."
This passive sentence is bothersome, not so much because of the passive voice, but because we don't know who "them" and "their" refers to until we get to the end. I could imagine writing this sort of passage:
Their best has been tried. (And it still wasn't good enough.)
That's how I see it, anyway. Thanks for the distraction from paper grading.
Beth
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