I. The preposition ¨de¨ is used:
1. with certain prepositions such as:
después de, antes de, adelante de, dentro de, fuera de...
2. with certain verbs:
depender de, enamorarse de,
II. The preposition "de" is always contracted when followed by the indefinite article el with the only exception of being part of a proper name:
de + el = del
Venimos del teatro Venimos de EL Salvador
Después del almuerzo