Sentence 1: Allie got a little scared. 
 Sentence 3: Later she realized that it was the landscapers 
 Sentence 4:  She then felt relieved 
 Sentence 5:  She went out to apologize to them 
 Option 1: All of the sudden she heard a mower right outside. 
 Option 2: All of the sudden she heard a fighter jet outside.