( ( If ( you ( ( put ( ( one teaspoon ) ( of salt ) ) ) ( in ( ( a glass ) ( of water ) ) ) ) ) ) ( , ( it ( ( has ( a ( low concentration ) ) ) . ) ) ) )
(ROOT (S (SBAR (IN If) (S (NP (PRP you)) (VP (VBD put) (NP (NP (CD one) (NN teaspoon)) (PP (IN of) (NP (NN salt)))) (PP (IN in) (NP (NP (DT a) (NN glass)) (PP (IN of) (NP (NN water)))))))) (, ,) (NP (PRP it)) (VP (VBZ has) (NP (DT a) (JJ low) (NN concentration))) (. .)))
If you put one teaspoon of salt in a glass of water, it has a low concentration.
(ROOT (S (NP (JJ Fresh) (NN water) (NNS biomes)) (VP (VBP are) (VP (VBN defined) (PP (IN by) (NP (JJ low) (NN salt) (NN concentration))))) (. .)))