在大学中，单独考察的题型几乎是没有的，但是语法知识点却贯穿整张试卷，下面小编为大家整理了英语四六级基础语法知识，希望可以为大家带来帮助，一起来学习一下吧。

英语知识：特殊的虚拟语气词should

1)Itisdemanded/necessary/apitythat…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)suggestedItis

(2)importantthat…(should)do

(3)apity(1)suggested,ordered,proposed,required,demanded,requested,insisted;(should)do

(2)important,necessary,natural,strangeapity,ashame,nowonder(3)Itissuggestedthatwe(should)holdameetingnextweek.Itisnecessarythathe(should)cometoourmeetingtomorrow.

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)doIsuggestthatwe(should)holdameetingnextweek.Heinsistedthathe(should)besentthere.

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。

Theguardatgateinsistedthateverybodyobeytherules.

判断改错:(错)Youpalefacesuggeststhatyou(should)beill.

(对)Yourpalefacesuggeststhatyouareill.

(错)Iinsistedthatyou(should)bewrong.

(对)Iinsistedthatyouwerewrong.

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。

Myideaisthatwe(should)getmorepeopletoattendtheconference.Imakeaproposalthatwe(should)holdameetingnextweek.