People get some of their value system from those taught by the cultures which they belong.

英訳に間違いが有れば正してください。

人間は自分たちが帰属する文化の中で学ばされた人々から彼らの価値体系を得る
People get some of their value system from those taught by the cultures which they belong.

ヒント
動詞の用法

答え to whichにするかbelong toにする

People get some of their value system from those taught by the cultures to which they belong.

belong to~
~に所属する