Can you please tell me how/when "in which" is used? This is a general question but I'll tell you where I see this. I see in most often as a modifier. If so, then when can it be used? Does the noun referrent need to be immediately preceding this modifier? "....., in which...." I haven't seen it today but I see it ALL the time and I'm not sure when it is allowed and when it is not.
Secondly, I did see "in which" used differently: Test Code (ETS) #37:
In the face of widespread concern about environmental waste, compact disc manufacturers are attempting to find a replacement for the disposable plastic box in which they package their product.
The correct answer to his question is A (repeating the sentence). Here "in which" is used differently. Can you please elaborate on how to use "in which"?
Thank you!