Could anybody please help me understand why the following underlined parts are kept as a present tense, not a past tense? In my understanding, if they are followed by the rules of the "sequence of tenses," they should be a past tense, no??

Example 1: It would be unforgivable if this turns out to be true.
Example 2: He told the directors he would sue them if the company takes anti-takeover measures.
Example 3: She said that she would not run if that political party fields its own candidate.

If the above unerlined parts were changed to the past tense, how would they sound?
These things have not yet happened -- but they still could.

1. We don't know yet if "it" is true or not. It may (in the future) turn out to be true... but it may not.

2. The company has not YET taken the anti-takeover measures. It may or may not do so in the future.

3. The same: The party has not yet fieled its own candidate, but it may.
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I see, so do you mean that I do not have to care about what is called "sequence of tenses" in these cases? In other words, these sentences are correct just as written in the present tense for the underlined parts? If so, does this principle apply to formal writing as well?
They are correct for formal writing.

Imagine they said "if in the future it turns out to be true" or "if in the future the party runs...."

These are imagining a scenario set in the future.
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But will that violate the conditional structure?
BellyBut will that violate the conditional structure?
Not really!

We use conditional statements to express propability. Here is a quick summary:

1. If the certainty is 100% (time independent), use present tense

If you don’t eat, you get hungry.
If you boil water, you get steam.

2. If the probability is about 50%, use present tense

If it turns out to be true / if it is true, she is correct. (Otherwise, she is wrong).

3. If the probability is small, use past tense

If I won the state lottery, I would buy you a car.

4. If the probability is 0% such as things that happened in the past that the outcome cannot be changed, use past perfect.

If I had won the recent state lottery, I would have bought you a car.

Happy New Year,
Hoa Thai
will that violate the conditional structure?
It just creates a "mixed conditional".

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