When _______how a statue from distant Greece could have appeared in China, researchers explained that no doubt this was a result of Alexander the Great’s influence.
Were it not for the snowy weather, we ________ all right.
________ more careful, his ship would not have sunk.
We ________ our lives had it not been for the policeman.
Wang Ling, one of my friends, is very good at English. He speaks English as if he ________ an Englishman.
The teacher agreed to the suggestion that the students ________ two weeks to prepare for the exam.