It is very necessary that he should be sent to the hosipcal immediately.
这句话为什么用了should而不是need? should和need的常用句式分别是什么呢?
答:这个句子中的that从句里的谓语动词,根据语法习惯与要求,是必须使用虚拟语气,即“ should do ”结构的。又例如:It is most important that you (should) keep your promise.
need 则是一般的用法,没有什么特别的要求。例如:This job needs skill and experience.