only引起的短语在从句中作状语时,主谓要倒装,能给些例句和典型讲解吗?

副词only置于句首,强调方式状语、 条件状语、 地点状语、 时间状语等状语时,主句要进行部分倒装.如果被only所强调的状语为状语从句,该状语从句不倒装,只对主句进行倒装.
例如：Only in a big city was it possible to buy a new wheelchair.只有在大城市里才能买到新轮椅.
Only when we had studied the data again did we realize that there was a mistake.只有当我们再次研究了这些数据的时候,我们才意识到出了一个错.
Only because there were some cancelled bookings did he get some tickets in the end.一些预订被取消了,他才得以买到了几张票.
注意：如果放于句首的only所修饰的不是状语时,该句不用倒装.
例如：Only John can save me.只有约翰能够救我.
Only some of the children passed the examination.只有几个孩子通过了考试.
给你几个相关的考题.
[考题1] ____ by keeping down costs will Power Data hold its advantage over other companies.(2006浙江)
A.Only B.Just C.Still D.Yet
[答案] A
[解析] 放于句首的only修饰方式状语by keeping down costs时,全句要进行部分倒装,而just,still,yet都无此用法.
[考题2] Only in this way ____ to make improvements in the operating system.(2003上海春)
A.you can hope B.you did hope
C.can you hope D.did you hope
[答案] C
[解析] only在题干中放于句首并修饰方式状语in this way,全句应进行部分倒装.又由于该句不是介绍过去的情况而是表述现实的一种状况,所以不应采用一般过去时,本题应选C.
[考题3] ____ can you expect to get a rise.(2001北京、 安徽春)
A.With hard work B.Although work hard
C.Only with hard work D.Now that he works hard
[答案] C
[解析] 题干中句子的结构显然为部分倒装语序,四个选项中只有C选项修饰方式状语with hard work的only可以引导倒装句,因此本题应选C.
[考题4] Only when your identity has been checked,____.(2003上海)
A.you are allowed in B.you will be allowed in
C.will you allow in D.will you be allowed in
[答案] D
[解析] 放于句首的only修饰when引导的时间状语从句时,主句应进行部分倒装(从句中不进行倒装).
[考题5] Only then ____ how much damage had been caused.(2006陕西)
A.she realized B.she had realized
C.had she realized D.did she realize
[答案] D
[解析] 放于句首的only修饰时间状语then时,主句应进行部分倒装,而且主句中“她意识到……”这一过去的动作对应的是“已导致损失”这一发生得更早的动作,所以下划线应与后面宾语从句中的过去完成时相呼应,采用一般过去时的形式,据此可以分别排除选项A、 B和C而选出D.