Unless, provided, ad long as, in case

unless

Unless means only if not. We use it when we say that if something does not happen,

something else will happen.

Unless we deal with the global warming problem, average temperatures will rise.

provided, as fong as + present simple

Provided and as long as mean only if.

Provided / as long as we reduce energy consumption, we can slow down global warming.

in case + present simple

This describes a possible situation we want to be prepared for.

Takean umbrella in case it rains.