How would you pronounce Τρελλός ανόητος! (crazy fool)in greek?

If you don't mind being punched in the face: trellos anoydos. Put the stress on the o in the first word and the first o in the second word. If you are addressing him, leave the s off the end of each word.

There is no need to say both words, either one would be enough.

1. Either you say Εισαι τρελλός ( και ανόητος )

EE-se tre-LOS ke a-no-EE-tos ( stress on caps

-se like in 'set', -tre like in 'trent', -ke like in 'kent; -a like in 'Al', -no like in 'not'

2. or you use Vocative form Τρελλέ ανόητε

trrre-LE a-no-EE-te ( stress on caps, when angry-you roll R a bit )

-le like in 'let', -te like in 'test'

trell-OS an-O-EE-tos

Pronounce the two vowels in the middle of ανόητος as separate syllables.