Simplify the following text for a Grade 12 native English-speaking person.
Original: While recording the Songbooks and the occasional studio album , Fitzgerald toured 40 to 45 weeks per year in the United States and internationally , under the tutelage of Norman Granz .
Simplified: While she was recording the Songbooks and the occasional studio album , Fitzgerald toured 40 to 45 weeks per year in the United States and internationally , with Norman Granz .