Assertion: backpack's pack | /r/ObjectUse | used by athlete
Facets:
value: sometimes
type: TEMPORAL
Source sentences:
text: Hydration packs, sometimes used by athletes and military personnel, carry water (in either a bladder or a rigid bottle) and have a tube connected to them from which the wearer can drink without removing the pack; this feature is also included in some more general-purpose hiking backpacks.