by RonPurewal Sat Jul 26, 2008 2:58 am
whereby is used in the same way as prepositional constructions such as in which or to whom.
as with those constructions, you can't use whereby unless you follow it with an independent clause, AND the surrounding text (if you remove whereby + following text) is also an independent clause.
examples:
the new method, whereby the age of an artifact can be ascertained to within fifty years, will revolutionize the study of ancient history.
notice the following:
* the age of an artifact can be ascertained to within fifty years, by itself, is an independent clause
* the new method will revolutionize the study of ancient history (the remaining part of the sentence) is also an independent clause
that's the deal.