second conditional

•The second conditional is used for conditions unreal, impossible, improbable, and so on. We always talk about conditions prevailing at the moment and not something that happened or could happen in the past.

•If I had a lot of money, I would buy a Ferrari.

•If we didn't have to work today, we could have a picnic.
Traducción: Si no tuviésemos que trabajar hoy, podríamos hacer un picnic

First conditional

•The first conditional speaking of the possible actions or events that may occur or not. the
conditional clause beginning with if and this is usually simple, while prayer
principal is generally in the future with "will" and describes what will happen if the condition is satisfied or not
comes to pass.

*If you study hard, you will pass your exams.

    *If he is busy now, I will come back tomorrow