Simplify the following text for a Grade 7 native English-speaking person.
Original: As persecutions of the Jewish population increased in July 1942 , the family went into hiding in the hidden rooms of Anne 's father , Otto Frank 's , office building .
Simplified: Persecution of Jewish people increased in July 1942 , and the family decided to hide . They hid in the secret rooms of her father Otto Frank 's office building .