The Continuous Tense
According to
Wikipedia:
In Spanish grammars, continuous tenses are not formally recognized as in English. Although the imperfect expresses a continuity compared to the perfect (e.g., te esperaba ["I was waiting for you"]), the continuity of an action is usually expressed by a verbal periphrasis (perÃfrasis verbal), as in estoy leyendo ("I am reading"). However, one can also say sigo leyendo ("I am still reading"), voy leyendo ("I am slowly but surely reading"), ando leyendo ("I am going around reading"), and others.