89. The task is hard, ____, the workers managed to finish it in time.
| A．therefore | B．otherwise | C．however | D．Yet |
The girlis singing an English song in the next room is Tom’s sister.
| A．whom | B．which | C．whose | D．who |
is known to us all, he is an excellent student in our class.
| A．Who | B．That | C．Which | D．As |
This is the reason he was late for class today.
| A．why | B．for that | C．which | D．that |
his being late again, he lost his job and had to stay at home.
| A．Because | B．As result of | C．In case that | D．Because of |
He was disappointed that his plan did not .
| A．go on | B．go off | C．go through | D．go out |