1） It is demanded / necessary / a pity + that…结构中的主语从句的谓语动词要用should 加动词原形， should 可省略。 句型： (1)suggested It is (2)importantthat…+ (should) do (3) a pity (1)suggested, ordered, proposed, required, demanded, requested, insisted； + (should) do (2)important, necessary, natural, strange a pity, a shame, no wonder (3)It is suggested that we (should) hold a meeting next week. It is necessary that he (should) come to our meeting tomorrow. 2）在宾语从句中的应用 在表示命令、建议、要求等一类动词后面的从句中。 order, suggest, propose, require, demand, request, insist, command, insist + (should) do I suggest that we (should) hold a meeting next week. He insisted that he (should ) be sent there. 注意： 如suggest, insist不表示"建议" 或"坚持要某人做某事时"，即它们用于其本意"暗示、表明"、"坚持认为"时，宾语从句用陈述语气。 The guard at gate insisted that everybody obey the rules. 判断改错: （错） You pale face suggests that you (should) be ill. (对) Your pale face suggests that you are ill. (错) I insisted that you ( should) be wrong. (对) I insisted that you were wrong. 3）在表语从句，同位语从句中的应用 在suggestion, proposal, idea, plan, order, advice等名词后面的表语从句、同位语从句中要用虚拟语气，即（should）+动词原形。 My idea is that we (should) get more people to attend the conference. I make a proposal that we (should) hold a meeting next week.