Some birds raise their feathers to make pockets of warm air to keep them warm, and some will molt and grow a new set of thick feathers for the cold weather.
(some; will molt; ) (some; grow; a new set of thick feathers for the cold weather) (Some birds; raise; their feathers; to make pockets of warm air to keep them warm) Context(Some birds raise,List([0, 16))):(Some birds; raise their feathers to make; pockets of warm air) Context(Some birds raise to make,List([0, 39))):(Some birds; raise their feathers to make pockets of warm air to keep; them)
Some birds raise,List([0, 16)) Some birds raise to make,List([0, 39))
some some Some birds Some birds Some birds
will molt grow raise raise their feathers to make raise their feathers to make pockets of warm air to keep
a new set of thick feathers for the cold weather
their feathers to make pockets of warm air to keep them warm
pockets of warm air
them