¿Durante o por?
¿Cuando se dice durante o por? Por ejemplo: "durante dos semanas" o "por dos semanas."
In your example, they are the same: "He estado enfermo por dos semanas" = "He estado enfermo por dos semanas" (I've been sick during two weeks).
I think they are the same when accompany time expressions. If "durante" precedes a situation, it cannot be replaced by "por": "Lo hice durante las vacaciones" =! "Lo hice por las vacaciones".
I already knew that, but I've been corrected for saying "por" instead of "durante."
In most contexts, both are correct, the exception being the example given by Chilotin, but I must say in Latin America we hardly ever use either to introduce a length of time, for example:
- Vamos a estar en España dos semanas = We'll be staying in Spain for two weeks
- Esperó veinte minutos = She waited for twenty minutes
- Llevo viviendo aquí cinco años = I've been living here for five years
- El espectáculo duró dos horas = The show lasted for two hours
- Hago ejercicio cuatro horas diarias = I exercise for four hours a day