These kettles were formed when chunks of ice broke off the glacier and buried themselves in the ground.
(These kettles; were formed; T:when chunks of ice broke off the glacier and buried themselves in the ground) (chunks of ice; broke off; the glacier) (chunks of ice; buried; themselves; in the ground)
These kettles chunks of ice chunks of ice
were formed broke off buried
T:when chunks of ice broke off the glacier and buried themselves in the ground
the glacier
themselves in the ground