Why En and not De

Question

En quien estas pensada (not sure I remembered the last word correctly).  In English this would be "of whom are you thinking?" so why is the Spanish En quien and not De quien.  (Accents do not appear to work)

Answer

Hola John
In Spanish the use of prepositions with relative pronouns (que, quién...) is sometimes different to English. As you mentioned before, in English you may say "To think of/about someone" however in Spanish we say "Pensar en  alguien", literally "to think in someone". This is why the right answer to that question is "¿En quién estás pensando?". (A possible answer to this question could be: "Estoy pensando en María").
I hope this clarified it.
Un saludo
Inma

Answer

Thank you.  (and people think learning English is confusing!)  I will try to remember.

Answer

Hi John, To help me remember this detail I like to think about how we sometimes will say "I can think ON that tomorrow". This is more similar to the Spanish "EN".

Answer

Ah, a question (old, but stil accurate) about 'en quién', as is in the kwiz, but not in the lesson!... shouldn't 'En quién' be mentioned in the lesson as well? (and indeed, referring to the '____ estas pensando?' Kwiz question