關於 這還用 的英文翻譯

這還用說嗎 = Tell me about it.

而 Tell me about it. 也能指「告訴我關於它的事」。

我們常常說的「廢話」有很多意思，以下是幾個常見的，必須分開講解:

你說的是真的嗎? (諷刺的意味，因為大家早就意料到了) = You don't say.
A: They won again.
B: You don't say. They got like half of the best players in the world on their team. (廢話，這還用你說！全世界的頂尖球員一半在他們的隊伍中)

當然啦，你白癡喔 = Of course. Are you a moron?
A: Does this car key go here?
B: Of course. Are you a moron? (廢話！你白癡喔)

沒用的話(說了跟沒說一樣) = not helping, being useless or uninformative, being unhelpful/not helpful
A: The car won't start because we ran out of gas.
B: You are not helping. We need gas, not useless talk. (廢話！我們需要汽油，不需要廢話)
The manual is badly written and not helpful. (說明書寫的很糟，都是廢話)
Your advice is mostly unhelpful. (你的建議大部分都是廢話)

你胡說八道/你亂說 = That's bullshit/nonsense. (nonsense = 鬼扯)
而這時候也能依情況使用 Give me a break. 例如:
C'mon give me a break. You know it's not true. (那是廢話！你知道那不是真的)

你馬拜託一下/你饒了我吧(諷刺對方太笨之類的) = Give me a break.
A: Does this car key go here?
B: Of course. Give me a break. (廢話！)

順道一提，trash-talk 並非「廢話」的意思，而是「嗆聲」的意思，例如:
If he keeps trash-talking his opponents he'll get his ass kicked.

Duh! = 狀聲詞，就是「廢話」的意思