这个前提是英语

前提 [词典] prerequisite; precondition; [逻] premise; presupposition; premiss; [例句]我不赞成经济发展应优先于环境保护这个前提。I disagree with the premise that economic development has priority over the environment.

......so long as we have the Invitation Letter from the organization there.

在...前提下:Under....pre-condition

on the premise

on accordance of

on condition thatYou will sucess on condition that you try your best

as long as...You can take my book as long as you can keep it good.