'Person's' in the Bible

Look! I observed that it is good and prudent to eat, drink, and enjoy all that is good of a person's work that he does on earth during the limited days of his life, which God gives him, for this is his allotment.

It is better to listen to a wise person's rebuke than to listen to the praise of fools.

Who is really wise? Who knows how to interpret this saying: "A person's wisdom improves his appearance, softening a harsh countenance."