They failed to notice that ducks were swimming in the main area where the water is set to fire.
(They; failed; to notice that ducks were swimming in the main area) (the water; is set; to fire; L:the main area) (They; to notice; that ducks were swimming in the main area) Context(They to notice,List([0, 21))):(ducks; were swimming; L:in the main area)
They to notice,List([0, 21))
They the water They ducks
failed is set to notice were swimming
to notice that ducks were swimming in the main area
to fire L:the main area
that ducks were swimming in the main area
L:in the main area