He tried to find out the way in which his best friend, John, learned English well.按文法詞類解析?謝謝!?

這是一個complex sentence
main clause: He tried to find out the way（受詞是不定詞片語to find out the way）
dependent clause: in which his best friend learned English well（它的先行詞為way，本附屬子句當作way的修飾語，為形容詞性質，屬限定性質）

John是his best friend的「同位語」，非限定性質。

He-----S
tried-----V
to find out-------inf.phr.,co-ord. to tried
in which-----which=rel.cl. when specifing the friend,John talking about, giving INFO about him;
learned---(has learned)----past participle
English well------going back to learned=learned well (adv);-----in which Eng.=O