释义：
like that ( this ) before 以前，之前
主要用作 not see ( feel, do ) anything like that ( this ) before 等形态，表示“没见过，没感觉过，没坐过”等表达方式，用于“吃惊”和“强调”。
例句：
Well, I have never seen anything like this before.
嗯，我从来没见过这种事情。
I've never felt like this before.
我从来没有过这种感觉。
I never did anything like that before.
我从来没做过那种事情。
I've seen things like this before.
我以前见过这种东西。
对话：
A: My stomach really hurts today.
今天胃好疼。
B: Have you ever felt like that before?
你之前疼过吗？
