three years; the third year / (education) the third school year / (figuratively) a long period of time, several years

three years; triennial / three years old

“a hundred days of sermonizing, one fart” → a metaphor for how something that one has put great effort into can come to nothing after even a slight mistake, much as a hundred days of serious spiritual study can be lost to the winds

a fountain pen

(literally) one side / everywhere, all around, the whole area / one viewpoint, one opinion or way of thinking / the front page of a newspaper

for the time being, for the present

the basics, a general idea

You should treasure every encounter, for it will never recur.

vicissitudes, the way that the world or a person prospers one day and declines the next

dotting the i's and crossing the t's