The word Decenia is misspelled against Decennia, which is plural of "Decennium"
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Decennia has double "nn" is mispronounced as "n"
Remember double 'NN' in between the strings dece & ia which should not be misspelled with single 'N'
Wrong Spelling: dece-n-ia
Correct Spelling: dece-nn-ia
Find more wrongly spelled words of Decennia to spell it well.