Background: 153 miners are still being trapped in a Chinese flooded coal mine. We don't know how many are alive and how many are dead. A China's English news channel reports:
If they did not survive, it would be China's most disastrous mining accident since 2007.
The report is written in subjunctive mood, but I think the hypothesis is real. Isn't it better to say:
If they do not survive, it will be China's most disastrous mining accident since 2007. ??
***** NOT A TEACHER *****
(1) What an interesting thread. I have always had problems with the conditional, so I am always attracted to such discussions.
(2) I am probably wrong, but I suggest that the sentence "If they DID not survive, it WOULD be China's worst such disaster" is defective.
(3) Jiaruchan says it comes from a Chinese English-language channel. Of course, the announcers do a wonderful job (we wish that we could speak Chinese half as well as they speak English). Nevertheless, let's be frank (in a gentle and respectful manner): Chinese English-language channels do not necessarily always use idiomatic English.
(4) I have come to a conclusion (probably wrong) after reading mmasny's post and Michael Swan's indispensable book:
(a) As mmasny suggested, this is NOT an unreal situation.
(b) Mr. Swan states: When we do not wish to suggest that a situation is unreal, we use ORDINARY TENSES with "if" -- the same as with other conjunctions.
(5) Therefore, I suggest we have at least two "good" sentences:
(i) If they do not survive (which is possible), it will turn out to be China's worst such disaster.
(ii) If they did not survive (the reports coming in now are pessimistic), this WILL (not "would" of unreal situations) be China's worst such disaster.
(a) Could we even say: If the miners have died (we have not heard anything from them in five days), this will turn out to be. ...
(iii) Mr, Swan gives this example that I have used (rightly or wrongly) as my evidence that the sentence at hand is not unreal:
If you did not do maths at school, you WILL find economics difficult.
Please pardon me if I am all wet.