Simplify the following text for a Grade 7 native English-speaking person.
Original: Written by Lewis between 1949 and 1954 , illustrated by Pauline Baynes and originally published in London between October 1950 and March 1956 , The Chronicles of Narnia has been adapted several times , complete or in part , for radio , television , the stage , and film .
Simplified: The books were written by Lewis between 1949 and 1954 , they were also illustrated by Pauline Baynes .