Sentence 1: Jack is a chemistry major. 
 Sentence 3: Last week, his friends didn't see him because he had so much work 
 Sentence 4:  He kept complaining about it when we saw him 
 Sentence 5:  However, we all think that he enjoys it 
 Option 1: His entire college career has been very easy. 
 Option 2: His entire college career has been difficult.