(Blank)
It seems as if
Apparently/probably
If in doubt
If you're not sure/if you don't care
Provided that
On the chance that/if and only if
If any
If there are some/if it's obvious
Rarely, if ever
Never/almost never
As long as
Once in a while/if and only if
Whether or not
If something is true or false/if something is false
Unless
If it doesn't happen that/if it happens that
If so
If desired/if true
If it weren't for/except in the case where