When should mientras or mientras que be followed by the subjunctive and when by the indicative? In both cases, how is mientras usually translated?
Mientras llueve, escucho música. (llueve: indicative)
While it rains, I listen to music
Mientras llueva, me quedaré en casa. (llueva: subjunctive )
As long as it rains, I'll stay at home.
"Mientras + indicative" implies mere simultaneity (at the same time something happens, another thing takes place).
"Mientras + subjunctive" suggests a condition (as long as something is happening ...)