Only when .
| A．did he arrive the meeting began | B．he arrived did the meeting begin |
| C．did he arrive the meeting begin | D．he arrived the meeting began |
— Bill, can I get you anything to drink?
— _______.
| A．You are welcome | B．No problem |
| C．I wouldn't mind a coffee | D．Doesn’t matter |
He did not regret saying what he did but felt that he____________ it differently.
| A．could express | B．would express |
| C．could have expressed | D．must have expressed |
He asked ______ for the violin.
| A．did I pay how much | B．I paid how much |
| C．how much did I pay | D．how much I paid |
Don't sit there ________ nothing. Come and help me with this table.
| A．do | B．to do | C．doing | D．and doing |
He made another wonderful discovery, _____ of great importance to science．
| A．which I think is | B．which I think it is |
| C．which I think it | D．I think is |