The word Retrogres is misspelled against Retrogress, a noun meaning "Retrogression."
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Retrogress has double 'ss' in the end mispronounced as 's'
Remember double 'SS' appears in the end of this word which should not be misspelled with single 'S'
Wrong Spelling:  retrogre-s 
Correct Spelling:  retrogre-ss 
Find more incorrect spellings of Retrogress to spell right way.