how long something lasts is a measure of how long that something is available
time is measurement. long_production_string is not tangible_thing. long_measure is linear_unit. σ_finite_measure is measure. long_thin_object is not tangible_thing. long_measure is not linear_unit. length is distance. long_thin_object is tangible_thing. long_production_string is tangible_thing. forever is long_time.