Conditional clauses
establish relations between two (or more) actions that
can only be realised if a condition is fulfilled. The
condition is defined in the phrase starting with if.
There are three different types of conditional
clauses.
The first type describes a condition in the past that
was not fulfilled and therefore the action depending
on this condition did not happen. This is called the
Irrealis of the past.
Example
If you had told
me I would have done it.
Wenn
du es mir vorher gesagt hättest, dann
hätte ich es gemacht.
There
is nothing that can change the fact that I didn't do it
(BUT if you had told me, I would have!)
The second type presents something that is not very likely
in the present, but still not actually impossible (not
as impossible as the first one).
This type is called Irrealis
of the present.
Example
If you knew you
would tell me.
Wenn
du es wüsstest, würdest du es mir
sagen.
The third one presents the condition as something quite
probable to be realized and therefore it is quite likely
that the depending action is going to be realised as
well. This type is called Realis
of the present.
learn-spanish-online.de
italian-online.de 
french-online.de 
