to accept that something is true before it has been proved

[ + that ] You're presupposing that he'll have told her - but he may not have. 你是在推测他早已告诉她了——但他可能没有这样做。

If an idea or situation presupposes something, that thing must be true for the idea or situation to work.

Investigative journalism presupposes some level of investigation. 调查报道要以一定程度的调查为前提。

[ + that ] All this presupposes that he'll get the job he wants. 所有这些都要以他能如愿找到工作为前提。