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How long a period of time has passed since then?
How long has passed since then?

I think that the second is grammatically incorrect although it carrys the same meaing as the first.
Is the second correct?
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LiveinjapanI think that the second is grammatically incorrect
You think right. Emotion: smile
CJ
(carries)
Comments  
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Should it be, how long has it passed since then?
Thanks, CJ.
Understand!
New2, it's a good question. I have no idea what it refers, so wait for other members.
New2grammarShould it be, how long has it passed since then?
It should be exactly as Liveinjapan has written it: How long a period of time has passed since then?
Alternate:
How long has it been since then?
CJ
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