When the Northern Hemisphere is tilted away from the sun--winter to us--the Southern Hemisphere is tilted toward it--summer to them.
(the Northern Hemisphere; is tilted; away from the sun) (the Southern Hemisphere; is tilted; toward it; T:When the Northern Hemisphere is tilted away from the sun)
the Northern Hemisphere the Southern Hemisphere
is tilted is tilted
away from the sun
toward it T:When the Northern Hemisphere is tilted away from the sun