听力原文:W: Professor Hook was so strange today. M: I noticed that too. He was talking so quietly and then not giving us any homework at all. Can you believe that? Q: What can be inferred about Professor Hook? (17)
A.
He usually talks quietly.
B.
He usually assigns homework.
C.
He didn't teach class today.
D.
He noticed that the students didn't do their homework..