Sentence 1: Sam has a big test in the morning. 
 Sentence 3: He went into class the next day and slept through the test 
 Sentence 4:  Sam failed the test 
 Sentence 5:  He vowed to never sleep through the test again 
 Option 1: He got plenty of rest the night before. 
 Option 2: He got extremely stressed so he stayed up all night.