sententious

to be moralizing, usually in a pompous sense

The old man, casting his nose up in the air at the group of adolescents, intoned sententiously, Youth is wasted on the young.

Chandak, a 13-year-old seventh grader at Seneca Falls Middle School, spelled "sententious",

Although Buddy did not know the word "sententious," the people he described were the embodiment of it -- licensed bores, as all aborigines seemed to be (so he implied), who had a proverb or a biblical passage for every reversal in life.

Note that you can build your GRE vocabulary via Vocab Assistant app hosted in facebook messenger.