*It is time we human beings to stop destroy the environment and make a difference.
依照主從分明的原則，It’s time 是主要子句，後面須接帶有附屬標記的補語，才能區隔主從關係，大致有兩種方式：
(1) 接 that 子句：It’s time that [someone] do [something] → 作為 time 的說明
It is time that we human beings stop destroying the environment and make a difference. → 說話者呼籲大家停下手邊的工作，不再破壞環境
(2) 接不定詞：It’s time for [someone] to do [something] → for...to 不定修飾
It is time for us human beings to stop destroying the environment and make a difference. → 在說話的同時，破壞環境的事情仍不斷發生
