I need hardly do something idiom formal
不用我说也知道
used to say that what you are going to say is obvious
I need hardly say what a pleasure it is to introduce our speaker. 我万分荣幸地来介绍我们的演讲者。
I need hardly remind you of the seriousness of the situation. 不用我提醒你也该知道局势的严峻。