a few years ago the belief became general that orange juice and milk should never be drunk at the same meal1.should never be drunk是一般过去的被动语态么?由情态动词should来体现be的时态?2.be drunk算是主要动词?be drunk是should never be drunk中的主要动词么~

问题描述:

a few years ago the belief became general that orange juice and milk should never be drunk at the same meal
1.should never be drunk是一般过去的被动语态么?由情态动词should来体现be的时态?
2.be drunk算是主要动词?
be drunk是should never be drunk中的主要动词么~

a few years ago (时间状语)the belief (主语)became(这里became相当于系动词BE的形式) general (表语)that部分做的是表语补足语that orange juice and milk (补语中的主语)should never be drunk(谓语) ...