Simplify the following text for a Grade 9 native English-speaking person.
Original: The common plural ( perhaps because of the association between the plurals lyrics and words ) , predominates contemporary usage .
Simplified: The plural lyrics was used only in referring to the words of several songs . That it is used for the words of a single song as its lyrics became increasingly common ( probably because of the association between lyrics and the plural form words ) , and is common in modern usage of today 's society .