1. (should)+动词原形
It +be动词+形容词(-able)(essential, odd, vital, absurd, regrettable, desirable…)+that从句 .
It +be动词+名词(pity,shame…)+that从句 .
It +be动词+过去分词(ordered, begged, voted, moved…)+that从句.
部分名词/动词(表示建议，劝告，决定等) +that从句 .
2. It’s (high, about) time that +动词过去式would rather +动词过去式
真题剖析
(1997) … I wouldn’t be truthful if I 47 say that teaching is hard work .47.
A. do
B. did
C. don’t
D. didn’t
(1993)…The Cairo newspapers the next day carried banner headlines about the student demonstration 52 , and they 53 that the professor be sent home.
53. A. ordered
B. pleaded
C. decided
D. demanded
练习：Years ago the experts warned us that the car-ownership explosion would demand a lot more give-and-take from all road users. It is high time that we__15__ this message to heart.
15. A. took
B. would take
C. will take
D. should take
(2003.3) It is edifying, and it is a source of inner satisfaction even __54__ other facets of life prove disappointing.
(even if other facets of life should prove disappointing.)54.A. shall
B.will
C.would
D.should