It is believed that on December 21st, 1891, the first basketball game in histry was played.
It is believed that 是固定用法吗
参考答案:据说,在1892年12月21日,历史上的第一场篮球比赛开始了.
It is believed中的it是形式主语,真正的主语是后面的主语从句that on December 21st, 1891, the first basketball game in history was played.
这样写的原因是主语太长了,如果放在句首会显得头重脚轻.其实believe后面还省略了by people.
同样的用法有很多,如: It is thought that you are a pretty girl.