Simplify the following text for a Grade 4 native English-speaking person.
Original: Pohnpei `` upon ( pohn ) a stone altar ( pei ) '' ( formerly known as Ponape ) is the name of one of the four states in the Federated States of Micronesia ( FSM ) , situated among the Senyavin Islands which are part of the larger Caroline Islands group .
Simplified: Pohnpei is one of the four states in the Federated States of Micronesia ( FSM ) . It is part of the Senyavin Islands group .