89. His term papers mainly _____ the history of social developments in Song dynasty.
34.John received an invitation to dinner,and with his work___,he gladly accepted it.
33.It is no _____arguing with Bill because he will never change his mind.
32.What kind of mistakes do you want to avoid ____full marks in your test?
31. _____his being late again,he lost his job and had to stay at home.
30.We don’t allow____here,but we can allow you ____in the next room.