Simplify the following text for a Grade 8 native English-speaking person.
Original: Several different national forms existed , with different lengths : the Scottish ell ( about 37 inches ) , the Flemish ell ( about 27 inches ) and the Polish ell ( 0.78 metres , about 31 inches ) .
Simplified: Several national forms existed , with different lengths , including the Scottish ell ( approx . 37 i ) , the Flemish ell ( 27 i ) , the French ell ( 54 i ) .