Complex sentence: Indian gauge,, is also compatible with Iberian gauge, although there are no actual railway connections between the two, but old Spanish and Portuguese rolling stock is reused in Argentina and Chile which use Indian gauge.
Split into simpler sentences: Indian gauge,, is also compatible with Iberian gauge, although there are no actual railway connections between the two. Despite this, old Spanish and Portuguese rolling stock have been reused in Argentina and Chile, both of which use Indian gauge.