Snow flakes are formed when the air is cold and water vapour freezes around a small speck of ice or dust.
(Snow flakes; are formed; T:when the air is cold and water vapour freezes around a small speck of ice or dust) (the air; is; cold and water vapour) (the air; freezes; around a small speck of ice or dust)
Snow flakes the air the air
are formed is freezes
T:when the air is cold and water vapour freezes around a small speck of ice or dust
cold and water vapour
around a small speck of ice or dust