( ( When ( this happens ) ) ( , ( ( ( the atom ) ( ( from which ) ( ( the electron ) ( is transferred ) ) ) ) ( ( becomes ( ( ( ( a ( positive ( ( ion or ) cation ) ) ) and ) ( ( the atom ) ( ( to which ) ( ( the electron ) ( is transferred ) ) ) ) ) ( becomes ( ( ( a ( negative ion ) ) or ) anion ) ) ) ) . ) ) ) )
(ROOT (S (SBAR (WHADVP (WRB When)) (S (NP (DT this)) (VP (VBZ happens)))) (, ,) (NP (NP (DT the) (NN atom)) (SBAR (WHPP (IN from) (WHNP (WDT which))) (S (NP (DT the) (NN electron)) (VP (VBZ is) (VP (VBN transferred)))))) (VP (VBZ becomes) (SBAR (S (NP (NP (DT a) (JJ positive) (NN ion) (CC or) (NN cation)) (CC and) (NP (NP (DT the) (NN atom)) (SBAR (WHPP (TO to) (WHNP (WDT which))) (S (NP (DT the) (NN electron)) (VP (VBZ is) (VP (VBN transferred))))))) (VP (VBZ becomes) (NP (NP (DT a) (JJ negative) (NN ion)) (CC or) (NP (NN anion))))))) (. .)))
When this happens, the atom from which the electron is transferred becomes a positive ion or cation and the atom to which the electron is transferred becomes a negative ion or anion.
(ROOT (S (SBAR (WHADVP (WRB When)) (S (NP (NNS electrons)) (VP (VBP move) (PP (IN from) (NP (CD one) (NN atom))) (PP (TO to) (NP (DT another)))))) (, ,) (NP (PRP they)) (VP (VBP become) (NP (NNS ions))) (. .)))