Question

 The great changes _______ have taken place _______ carrying out the economic reform in our country.

A．may not; unless	B．could not; without
C．never; but for	D．would; besides

Answer 1

B

试题分析：考查虚拟语气。题中without相当于if引导的条件虚拟语气，与过去事实相反，故主句用could have done。句意：要不是在我们国家实施经济改革，不可能发生巨大的变化。故B正确。