3B1 expresses question about the occasion, indeed expects it not to occur. 3B2 expresses uncertainty, it would or might not materialize. 3B3 expects that it's going to take place. I seldom see any in the 4 variations outlined in the initial write-up. All four of such variations are acceptable. 1 https://petskyonline-onlinestrore.blogspot.com/2025/07/top-10-aquarium-essentials-for-new-fish.html