“until” (l.26) can be correctly replaced by by.

the use of “is no fan of” (l.18) instead of isn’t a fan of emphasizes the negative idea in the sentence.

“generous streak” (l.11) can be translated as veia generosa in Portuguese.

“put at” (l.7) is the same as estimated as.

“intends” (l.6) is synonymous with pretends.

“By the end” (l.6) can be replaced by At the end.

“given away” (l.3-4) can be replaced by wasted.

Bill Gates has already contributed with a substantial amount to his Foundation.

Mr. Gregorian has no qualms about making a competition of giving.

Mr. Gregorian thinks that being secretive about giving encourages others to donate more freely.