什么叫做虚拟啊?答:其他形式的虚拟语气 (⒈) it is +necessary等形容词后,that主语从句中虚拟形式使用,这类形容词包括necessary, important, essential, imperative, urgent, preferable, vital, advisable等,例如It is necessary that you listen to the teacher carefully.或者It is essential that you be able to pronounce every ...