Page "Grammatical aspect" Paragraph 27

** For some verbs in some languages, the difference between perfective and imperfective conveys an additional meaning difference ; in such cases, the two aspects are typically translated using separate verbs in English.

In Greek, for example, the imperfective sometimes adds the notion of " try to do something " ( the so-called conative imperfect ); hence the same verb, in the imperfective ( present or imperfect ) and aorist, respectively, is used to convey look and see, search and find, listen and hear.

( For example, ηκουομεν ēkouomen " we listened " vs. ηκουσαμεν ēkousamen " we heard ".

) Spanish has similar pairs for certain verbs, such as ( imperfect and preterite, respectively ) sabía " I knew " vs. supe " I found out ", podía " I was able to " vs. pude " I succeeded ( in doing something )", quería " I wanted to " vs. quise " I tried to ", no quería " I did not want to " vs. no quise " I refused ( to do something )".

Such differences are often highly language-specific.