This letter is to ask for your support in remembering your fellow classmate.
( ( This letter ) ( ( is ( to ( ( ask ( for ( your support ) ) ) ( in ( remembering ( your ( fellow classmate ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT This) (NN letter)) (VP (VBZ is) (S (VP (TO to) (VP (VB ask) (PP (IN for) (NP (PRP$ your) (NN support))) (PP (IN in) (S (VP (VBG remembering) (NP (PRP$ your) (JJ fellow) (NN classmate))))))))) (. .)))
The purpose of the letter is to ask for support in remembering your classmate.
( ( ( The purpose ) ( of ( the letter ) ) ) ( ( is ( to ( ( ask ( for support ) ) ( in ( remembering ( your classmate ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN purpose)) (PP (IN of) (NP (DT the) (NN letter)))) (VP (VBZ is) (S (VP (TO to) (VP (VB ask) (PP (IN for) (NP (NN support))) (PP (IN in) (S (VP (VBG remembering) (NP (PRP$ your) (NN classmate))))))))) (. .)))