formal adverb
of the thing mentioned 在其中；由此
Is the property or any part thereof used for commercial activity?
这一财产或其中任何部分有用于商业活动吗？
States differ in standards for products and the labelling thereof.
各州的产品标准不同，其标签也不同。
Money, or the lack thereof , played a major role in their marital problems.
钱，或者说没钱，是造成他们婚姻矛盾的主要原因。