合句中 定语从句中的先行词怎么找 例：Uluru is the big rock .It's also known as

合句中 定语从句中的先行词怎么找 例：Uluru is the big rock .It's also known as Ayers Rock.3Q
再例:Syndey House Opera was a symbol of Australia.It was used as the symbol of the 2000 Olympic.Australia is the country.Most British people would like to visit it.还有给你一句定语从句的中文怎么把它翻译成英文定语从句.要方法.例：篮球是许多人喜爱的运动.正在树下说话的男孩是你的弟弟吗?我昨天读的书很有趣.你认识今天早上敲门的那个男人吗?