_______ the calculation is right, scientists can never be sure that they have included all variables and modeled them accurately.
| A．Even if | B．As far as | C．If only | D．So long as |
The problem lies __________ we are now giving him a fish, not teaching him to fish.
| A．in that | B．on that | C．in which | D．on which |
We were lucky to have survived the train accident. _____, the first and last car were smashed.
| A．On top of this | B．What was worse | C．As it was | D．So it was |
Only after being attacked by the Japanese in Pearl Harbor ___in the Second World War thoroughly.
| A．had America involved | B．was America involved |
| C．America had involved | D．America was involved |
Mum, please let us, Mary and me, go to Jack’s birthday party tomorrow, ______?
| A．can you | B．will you | C．shall we | D．may we |
--- Sorry to have interrupted you. Please go on. --- Where was I?
--- You ________ you didn’t like to be prejudiced against.
| A．said | B．had said | C．were saying | D．had said |