这个句型与：It is said/ suggested/ believed that- 一样.
It 是形式主语,代替真实的主语从句 ...that some precautions...from.
因为主语从句太长、太重,故挪到后面,保持平衡.
也可以说：We/People highly recommend= suggest that.
e.g.People believe that hard work must lead to success.
= It is believed that hard work must lead to success.
Got it?