A kettle lake occurs where a chunk of ice was left behind in the till of a retreating glacier.
(A kettle lake; occurs; L:where a chunk of ice was left behind in the till of a retreating glacier) (a chunk of ice; was left; behind; L:in the till of a retreating glacier)
A kettle lake a chunk of ice
occurs was left
L:where a chunk of ice was left behind in the till of a retreating glacier
behind L:in the till of a retreating glacier