itis形容词that句型虚拟should可以省
it is 形容词that
itbe形容词that虚拟
it is形容词 that
itisnecessarythat的虚拟
it is high time that虚拟语气 should可以省
itistimethat的虚拟语气
it is advisable that虚拟
it is that 虚拟
it is strange that 虚拟
