YAMATO2201
Senior Member
- Joined
- Dec 29, 2016
- Member Type
- Student or Learner
- Native Language
- Japanese
- Home Country
- Japan
- Current Location
- Japan
In my high school days, all my English teachers claimed that "unless" and "if not" were always interchangeable. But, some years later, I encountered a sentence to which such claim cannot be applicable. I thought about "unless" for some time and came to the conclusion that "unless" means "if and only if not". In order to confirm my conclusion, I examined some sample sentences from my textbooks.
Please look at the sentences below:
(A) I'll go unless it rains.
(B) I'll go if and only if it does not rain.
(C) I'll go if it doesn't rain.
(D) I'll be surprised if Mary doesn't win.
(E) I'll be surprised unless Mary wins.
My observations on these sentences are:
[1] (A) and (B) have the same meaning (according to my conclusion above), although I suppose that native English speakers would not use (B) under any circumstances.
[2] (C) is superficially different from (B), but I think that (C) connotes "I won't go if it rains." Hence (B) and (C) are the same in meaning.
[3] (D) and (E) are not interchangeable. I think that (E) is incorrect or absurd.
Am I right?
Thank you.
-------------------------------------------------------------------------------------
This post has been corrected. The original post contains a careless mistake.
The second (D) in [3] in the original post should be (E).
Please look at the sentences below:
(A) I'll go unless it rains.
(B) I'll go if and only if it does not rain.
(C) I'll go if it doesn't rain.
(D) I'll be surprised if Mary doesn't win.
(E) I'll be surprised unless Mary wins.
My observations on these sentences are:
[1] (A) and (B) have the same meaning (according to my conclusion above), although I suppose that native English speakers would not use (B) under any circumstances.
[2] (C) is superficially different from (B), but I think that (C) connotes "I won't go if it rains." Hence (B) and (C) are the same in meaning.
[3] (D) and (E) are not interchangeable. I think that (E) is incorrect or absurd.
Am I right?
Thank you.
-------------------------------------------------------------------------------------
This post has been corrected. The original post contains a careless mistake.
The second (D) in [3] in the original post should be (E).
Last edited: