Winter Solstice... occurs at the beginning of the winter season (when the tilt of the Earth's axis is pointing away from the Sun).
(Winter Solstice; occurs; T:at the beginning of the winter season) (the tilt of the Earth's axis; is pointing; away from the Sun)
Winter Solstice the tilt of the Earth's axis
occurs is pointing
T:at the beginning of the winter season
away from the Sun