Sometimes people use the light, and they take the observed light times the mass to light ratio for the object, and they get the mass that way.
(people; use; the light; T:Sometimes) (they; get; the mass) (they; take; the observed light times; to light ratio for the object) Context(they take,List([36, 45))):(they; take the observed light times to light; ratio for the object)
they take,List([36, 45))
people they they they
use get take take the observed light times to light
the light T:Sometimes
the mass
the observed light times to light ratio for the object
ratio for the object