过去完成时的翻译Until recently, the disease had not been observed in Nebraska production fields at severe levels for many years.

until recent times,unknown to man.怎么翻译呢? 过去完成时的翻译Until recently, the disease had not been observed in Nebraska production fields at severe levels for many years. 英语翻译until的翻译方法 not until 能用于过去完成时吗 英语中until的用法I didn't sleep until my mother_________(reach)home.这种情况下,until后面跟什么时态啊,现在完成时,过去完成时还是什么? until 和过去完成时的的用法he stayed here until i came back和he had stayed here until i came back有什么区别?过去完成时是过去时的分支还是完成时的分支? 英语过去完成时过去完成时的含义 not until和过去完成时过去完成时是加在not那边还是until后面新概念好像写了个I had not understood the problem until he explained it.但翻译是在他解释之前我不懂这个问题不是说not until是 直到……才吗 not until在句首可以用过去完成时吗? 什么是过去完成时_过去完成时的用法 not until的过去完成时有这样两个句子：1.The young man did not wake up until the bed had struck the ground.2.I had not understood the problem until he explained it.哪一个正确?具体讲讲原因呗. 过去完成时的标志? 过去完成时的标志是什么? 英语的过去完成时 过去完成时的被动语态 过去完成时的定义 过去完成时的定义是什么? 过去完成时的句式是什么?