Sentence 1: Pam was throwing a party for her friends. 
 Sentence 3: Then she decorated her house 
 Sentence 4:  Soon Pam's friends arrived and began dancing 
 Sentence 5:  Everyone had a fantastic time at Pam's party! 
 Option 1: Pam had everything done and then realized she forgot to invite everyone. 
 Option 2: She invited everyone over and ordered pizza.