“on the tip of my tongue”可不是“在我的舌头尖上”，真实含义是就在嘴边，但是就是说不出来；呼之欲出；话到舌尖。

【例句】
The song is very familiar to me. It's on the tip of my tongue but I just can't get it out.
这首歌对我来说很熟悉，就在我嘴边，可是就是说不出来了。

I have her name on the tip of my tongue.
她的名字就在我嘴边，却说不出来。