1)在主语从句中的用法：
|
It
is |
可用的词有三类 |
that |
(should)do |
|
suggested,
ordered, required, proposed, demanded, requested, insisted, decided等 |
|||
|
important,
necessary, natural, strange，
imperative(紧急的),
surprising, funny等 |
|||
|
a
pity, a shame, an honour, no wonder等 |
2)在宾语从句中的用法：
在表示命令、建议、要求等一类动词(如order, suggest, propose, require, demand, request, desire, command, insist, advise等)后面的从句中， 谓语动词应用(should)do。
3) 在表语从句，同位语从句中的用法：
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。
22. Jane’s face suggested that she _____ ill, and her parents suggested that she _____ a medical examination.
A. be; should have B. was; have
C. should be; had D. was; has