_______ we are doing now has never been done before.
| A．That | B．What |
| C．Which | D．Whether |
The play went along well until the middle of Act 2 ,_____the excitement began .
A soB but C when D which
He is a man with rich experience , from ______much can be learned .
A whom B which C whereD what
There was _____to prevent the accident .
A something could doB anything we could do
C nothing we couldn’t doD nothing we could do
---- Is Mary coming to the concert?
---- I think ________.
| A．yes | B．it | C．that | D．so |
---- Have you been here long?
---- _______.
| A．No, not very long | B．Not much long |
| C．Yes, only little long | D．No, only yesterday |