The professor explained the problem and solution 'thereof'. [=the problem and the solution of the problem]
A will or any part 'thereof' [=any part of a will] may be revoked by a subsequent will.
The problem is money, or (a/the) 'lack thereof'. [=the problem is a lack of money]
(..) Amendment one: Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; - or abridging the freedom of... - stop. Regurgitating memorized amendments isn't what I'm asking for. Just tell me something about (..)2016 Captain Fantastic