vs
QUICK ANSWER
"Dentro de" is a preposition which is often translated as "inside", and "encima de" is a phrase which is often translated as "on". Learn more about the difference between "dentro de" and "encima de" below.
dentro de()
A preposition is a word that indicates the relationship between a noun and another word (e.g., He ran through the door.).
2. (time limit)
encima de()
A phrase is a group of words commonly used together (e.g., once upon a time).