In the early season, most of the food brought back to the nest by the workers is partially-chewed remains of insects, caterpillars, and worms.
(the food; brought; back to the nest; by the workers) (most of the food; is; partially-chewed remains of insects, caterpillars, and worms; L:In the early season)
the food most of the food
brought is
back to the nest by the workers
partially-chewed remains of insects, caterpillars, and worms L:In the early season