1. 先行词是the people.
2. 定语从句从in whose village开始,到before结束。
主句为the people have lived a happy life.
整句为:the people (in whose village I taught before) have lived a happy life.
打括号者为定语从句。
翻译:我以前教过书的村子里的人们过着快乐的生活。
3. 定语从句中I taught无宾语。此处taught(teach)视为不及物动词。
关系代词whose=the people's即先行词的所有格形式。
定语从句的完整句子为:
in whose village I taught before
=I taught in whose village before
=I taught in the people's village before
参考资料:原创回答团(本人第159号会员)