Word 1:prude (PROOD)
Meaning: Someone who is concerned about propriety and decorum to the extreme.
Example Sentence: Her attitude is prudish in almost all things.

Word 2: Prudent (PROOD n’t)
Meaning: Cautious and discreet in conduct
Example Sentence: Her prudent investments helped them through rough times.

Example Sentence using both words:
It was difficult to believe that the prudent man was actually a prude.