( ( ( High frequency ) ( -LRB- ( HF -RRB- ) ) ) ( ( is ( ( ( ( the ( ITU designation ) ) ( for ( ( the range ) ( of ( radio ( frequency ( electromagnetic waves ) ) ) ) ) ) ) ( -LRB- ( ( radio waves ) -RRB- ) ) ) ( between ( 3 ( and ( 30 MHz ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (JJ High) (NN frequency)) (PRN (-LRB- -LRB-) (NP (NNP HF)) (-RRB- -RRB-))) (VP (VBZ is) (NP (NP (NP (DT the) (NNP ITU) (NN designation)) (PP (IN for) (NP (NP (DT the) (NN range)) (PP (IN of) (NP (NN radio) (NN frequency) (JJ electromagnetic) (NNS waves))))) (PRN (-LRB- -LRB-) (NP (NN radio) (NNS waves)) (-RRB- -RRB-))) (PP (IN between) (NP (CD 3) (CC and) (CD 30) (NNS MHz))))) (. .)))
High frequency (HF) is the ITU designation for the range of radio frequency electromagnetic waves (radio waves) between 3 and 30 MHz.
(ROOT (S (NP (NNP Am) (NN radio) (NNS waves)) (VP (VBP exist) (PRT (RP in)) (NP (DT the) (ADJP (QP (CD 540) (TO to) (CD 1600))) (NN khz) (NN frequency) (NN range))) (. .)))