( ( ( ( MIDDLE ATMOSPHERE ) , ) ( THERMOSPHERE-IONOSPHERE ( COUPLING SYSTEM ) ) ) . )
(ROOT (NP (NP (NNP MIDDLE) (NNP ATMOSPHERE)) (, ,) (NP (NNP THERMOSPHERE-IONOSPHERE) (NNP COUPLING) (NNP SYSTEM)) (. .)))
MIDDLE ATMOSPHERE, THERMOSPHERE-IONOSPHERE COUPLING SYSTEM.
(ROOT (S (NP (NNP Thermosphere)) (VP (VBZ is) (NP (DT the) (JJ upper-most) (NN atmosphere))) (. .)))