An ItemHookup groups together the hookups for the various properties of an individual object, typically an item in an IndependentSequenceHookup. It may also track one or more boxes which belong entirely to this item. For example, a LexEntry might have one paragraph which holds most of its content (the text part), and another which holds its pictures. The ItemHookup would track the two paragraphs as well as the hookups which hold the various properties of the LexEntry. If the senses of the entry are displayed as a sequence of strings within the one paragraph, the ItemHookups for the senses would not track any box, just the individual string hookups (or possibly another layer of IndependentSequenceHookup holding example sentences, etc.).