Sentence 1: Dan stayed up late playing video games. 
 Sentence 3: Chemistry class was extremely boring for Dan 
 Sentence 4:  He fell asleep and started snoring loudly 
 Sentence 5:  Dan's teacher slammed books on his desk and Dan jumped up 
 Option 1: He was so tired the next morning. 
 Option 2: He was so tired the next morning that he didn't go to school that day.