( ( In geography ) ( , ( ( a delta ) ( ( is ( ( an ( alluvial ( triangular deposit ) ) ) ( formed ( at ( ( diverging mouths ) ( of ( a river ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (NN geography))) (, ,) (NP (DT a) (NN delta)) (VP (VBZ is) (NP (NP (DT an) (JJ alluvial) (NN triangular) (NN deposit)) (VP (VBN formed) (PP (IN at) (NP (NP (VBG diverging) (NNS mouths)) (PP (IN of) (NP (DT a) (NN river)))))))) (. .)))
In geography, a delta is an alluvial triangular deposit formed at diverging mouths of a river.
(ROOT (S (NP (NNP Delta)) (VP (VBZ is) (NP (NP (DT a) (NN triangular) (NN feature)) (SBAR (WHNP (WDT that)) (S (VP (VBZ is) (VP (VBN formed) (SBAR (WHADVP (WRB when)) (S (NP (DT a) (NN river)) (VP (VBZ empties) (PP (IN into) (NP (NP (DT a) (JJ large) (NN body)) (PP (IN of) (NP (RB still) (NN water)))))))))))))) (. .)))