With idiomatic sentences all we can do is to try writing the sentiment the best way we can in our own language. This leads to some oddities like here where "Eu faço" seems to be translated as "I am". Trying to understand idiomatic usage by literal translation is often doomed to failure. Perhaps Brazilians regard the community as a big pie and think "I make (up) part of this pie".
Well, "desta" means "of this" (not "of the") so that could be one reason it didn't work.
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@mk0, if "parte" was meant as a verb (not necessarily on this phrase but in any other), it would be conjugated for the 1st person of the singular, so it would be "eu parto".
For "você/ele/ela" it's a bit more complicated, because "você parte/ele parte/ela parte" is the correct conjugation. But in this case "faço" is the one acting like a verb so "parte" has to be the noun. You can put two verbs in a row in a Portuguese sentence, but the second verb will have to be in the infinitive form (ex: "eu faço partir" - "I make it leave" or "I make it break").
The translation I was given was "I take part of this community" - where do you take it? It ought to be "I am part" or "I make up part". I think the only time you'd use "take" is in this sort of expression: "I take part in this community" - but that would translate something else, as you can be part of a community without taking part in it....