Simplify the following text for a Grade 8 native English-speaking person.
Original: The Treaty of Berlin was signed on July 28 , 1742 between Austrian archduchess Maria Theresa and Frederick II of Prussia . Based on the terms of the treaty , Maria Theresa ceded most of Silesia to Frederick except for the districts of Troppau , Teschen , and JÃ gerndorf .
Simplified: Based on the treaty , Maria Theresa gave most of Silesia to Frederick .