If only yesterday were tomorrow. What day is today in the sentence?

If yesterday was tomorrow, then today is Friday. First of all, this is because the meaning of English titles and translated names does not necessarily match. After all, China has a different context. The first case: if only yesterday is tomorrow, it can only be understood as yesterday (true), today (true) {tomorrow (true), yesterday (false), today (false) and tomorrow (false), so if today (false) is Friday, today (true) is Wednesday. Many people say that Sunday is ok in English, but not in Chinese, because the first sentence defines yesterday as hypothesis and tomorrow as truth. It is impossible to write yesterday (false), today (false) {yesterday (true), tomorrow (false)}, today (true), tomorrow (true), if you exchange yesterday and tomorrow in the sentence. In the second case, the question "What day is today in the sentence" can be regarded as a substitute for the previous sentence "Today" in Chinese, and the "Today" in the sentence has become "Today (False)" because of the assumption in the previous sentence, so the question can be understood as "What day is today (False) in the sentence? Answer on Friday. Generally speaking, this is caused by ambiguity caused by English translation into Chinese. If the question is translated into today, there will be no ambiguity. But the answer can only be chosen on Wednesday and Friday, because the timeline will not change anyway, and English questions can't be translated randomly, otherwise there will be jokes.