Wow, this part of Japanese grammar is SO complicated.
So I can use
- と
- たら
- ば
- なら
Obviously, not all can be used, based on the context of the sentence. It’s figuring out the context of the sentence that’s the problem.
The way I am trying to learn it is that there is an antecedent part of the sentence, and a consequent part of the sentence.
- I go to Japan (antecedent)
- I will visit Osaka and eat a lot (consequent)
In English, I’ve got one word for conditional, if.
- If I go to Japan, I will visit Osaka and eat a lot.
In English, there is also the word when, which isn’t really conditional. It’s a sure thing.
- When I go to Japan, I will visit Osaka and eat a lot.
There is also whenever, which again is more of a done deal than a conditional occurrence.
- Whenever I go to Japan, I visit Osaka and eat a lot.
As I understand it now, the Japanese conditional form covers all three of these: if, when, whenever. But it also includes whether you are referring to yourself in both parts (A and C) of the sentence or not, whether the action took place in the past, whether the antecedent contains a stative predicate (what?), and so on.
Well, I guess the only way to get good at it is to keep studying.