If there __________ no air, people would die.A、wereB、isC、beD、been

If there were no exams, we should have _______ at school.A、the happiest timeB、a more ha

______no air or water, there would be no life in the world.A．There wasB．There wereC．Is the

Charging－air pressure increases if there is incorrect combustion and drop in the _____ of

If there were no polysemy, Chinese______ much easier to learn.A．will beB．could have beenC．

If there were no subjunctive, English______much easier to learn.A．could have beenB．would b

If there were no subjunctive mood, English_____much easier to learn.（2009)A．could have bee