45.If…
[the hypothesis is quite probable]
[the hypothesis is not really envisaged]
[in the end, the hypothesis has not come true]
he they we 1 this, IF do (not do)
the situation
things
worse.
better.
WILL be
he they we 2 this, IF did (not do)
the situation
things
worse.
better.
WOULD be
he
they
we
3
this,
IF              had (not) done   
the situation
things
worse.
better.
WOULD have been