他 / 不愿 / 让 / 父亲 / 留下 / 的 / 书房 / 荒弃 / 周末 / 常常 / 进去 / 打扫

他不愿让父亲留下的书房荒弃，周末常常进去打扫。

He did not want his father's study to fall into disuse, so he often went in to clean it on weekends.