Zero+Conditional

__USES__

 * Situations that are always true if something happens.
 * Example: __If I eat__ too much, __I have__ stomachache.
 * (!) Usually, "if" can be replaced by "when".
 * Example: __ When I eat __ too much, __ I have __ stomachache.

__FORM__

 * If clause [present simple] +,+ Main clause [present simple]
 * We can use an inversion in Zero Conditional, without using the comma between the Main clause and the If clause
 * If she has time, we have a coffee / We have a coffee if she has time.