1．But perhaps one of the most beautiful and extraordinary marathons ever is the Great Wall Marathon, which most competitors find is the toughest course to run. [信息提取]　which most competitors find is the toughest course to run是含有插入语(most competitors find)的定语从 句。 [例句仿写]　在公共汽车上我看到一个我以为是你哥哥的学 生。 On the bus I saw a student __________________________________.

who I thought was your brother

Ⅲ.句型搜索