Sentence 1: Brandon had just qualified as a substitute. 
 Sentence 3: But when he stepped into the classroom, he encountered screaming kids 
 Sentence 4:  He tried to calm down the rowdy hooligans, but to no avail 
 Sentence 5:  As he went to bed that night, he was dreading the next day 
 Option 1: He was confident he'd be great at it but had no classes scheduled yet. 
 Option 2: As he prepared for his first class, he was confident he'd do great.