Breakdown of Si el cordón de tus zapatillas se suelta, tienes que atarlo otra vez.
Questions & Answers about Si el cordón de tus zapatillas se suelta, tienes que atarlo otra vez.
Because after si for a real, possible condition in the present or future, Spanish normally uses the present indicative, not the subjunctive.
So:
- Si el cordón ... se suelta = if the lace comes undone / if the lace gets loose
This is a normal real-life condition, so se suelta is the expected form.
You would not say si ... se suelte here.
Soltarse is a very common pronominal verb. Here it means something like:
- to come loose
- to come undone
So el cordón se suelta means the lace loosens/comes undone by itself, rather than someone actively loosening it.
Compare:
- Suelto el cordón = I loosen the lace
- El cordón se suelta = the lace comes loose
That se often gives the idea that the thing undergoes the change itself.