They feel as though the mans presence is ominous in a way, saying he's sullen would suggest he's viewed poorly by them
Homework exists so the school can reinforce what you learned at school.
Ethos is a mode of persuasion used to convince the audience. It is one of three artistic proofs (ethos, pathos, and logos).
Ethos is also known as ethical appeal and convinces your audience of credibility and character. It is used to prove you are worth listening to. Ethos can be developed by choosing language that is appropriate for the audience and topic (this also means choosing the proper level of vocabulary), making yourself sound fair or unbiased, introducing your expertise, accomplishments or pedigree, and by using correct grammar and syntax.
