如果，倘若，倘若情况是这样，倘若事实如此

1. if, in case, if it is the case that, if it is true that

auxiliary

至于，关于

2. as for, on the topic of

auxiliary

如果情况如此，那么，既然如此

3. if that's the case, if so, that being the case

conjunction colloquial abbreviation

如果可能的话，如果情况允许的话

4. if possible, if circumstances allow

conjunction