It goes without sayig that we cannot be young forever. 毋容置疑，我們不可能永葆青春（不可能青春常駐，不可能青春常在）。

It goes without sayig that...不言而喻, 理所當然, 不消說, 不言自明, 不用說，毋庸置疑。It是主語，goes是謂語，without sayig...作狀語；saying ...是動名詞短語作介詞without的賓語；that引導的是賓語從句，作動名詞saying的賓語。如：

And it goes without saying that he hired the best chefs for his kitchen. 而廚房更是不用多說，他僱傭了最好的廚子來負責他的飲食。

Anne just told me she can"t go with us. It goes without saying we"re disappointed. 安娜剛告訴我不能和我們一起去了，不用說，我們都很失望。

First, it goes without saying that you must carefully prepare the materials you are going to play. 首先，不得不說的是你必須要仔細準備好你演奏所需要的一切材料。

It goes without saying that in order to speak good English, we must first of all learn good pronunciation. 不言而喻，為了講好英語，首先必須學好發音。