Question

英语达人请进，帮忙分析这句英文的结构 语法 句式，谢谢

句子：They said it might have been prevented had he received the dental care he needed

Answer 1

宾语从句：it might have been prevented had he received the dental care he needed （用了虚拟语气，对过去的假设）
状语从句：had he received the dental care he needed （省略了if ，把助动词had提前）
定语从句：he needed （省略了关系词that或者which）
整句话的意思是：大家说如果他接受所需的牙齿治疗，就能避免（这种病）了。

Answer 2

主句：They said (他们说...) 后面的都是宾语从句，是“说”的内容。

宾语从句中个的第1个分句：it might have been prevented 这事本可以被避免（实际上还是发生了，此处为虚拟语气）

宾语从句中个的第2个分句：had he received the dental care he needed (倒装句，正常语序为if he had received the dental care he needed）如果他接受了他所需的口腔治疗的话 （此处也是虚拟语气，实际上他没有接受治疗）

第2分句中的一个定语从句：“he needed"作定语从句修饰“the dental care”，意为“他所需的口腔治疗”

Answer 3

1）这句你可能不理解had he received the dental care he needed 这一部分。其实这一部分等于if he had received the dental care he needed，是个虚拟语气的条件从句或非真实性条件从句。
2）it might have been prevented had he received the dental care he needed 是间接引语。

追问

虚拟语气还是不太明白，if he had received......为什么就变成了had he......?

追答

if somebody had had done 可以转换成 had sobody done，两个结构意思一样。

Answer 4

这个句子是：They said （主句）
had he received the dental care he needed如果他接受了所需的牙齿护理（事实是没有，虚拟语气）
it might have been prevented 这件事情本来可以避免（事情是已经发生了，没有避免掉）

Answer 5

这将会保护他的牙齿如果他接受必要的牙齿护理