How to know the correct translation-I'm in a Spanish class and we are supposed to translate sentences in their correct way. My question is, how do I know if I am supposed to translate a sentence in Preterite or in imperfect. For example, how do I know if " Carlos tried to open the door, but it was locked." is preterite or imperfect?

Generally speaking, the preterite is used for actions in the past that are seen as completed, while the imperfect tense is used for past actions that did not have a definite beginning or a definite end.

Explanation:

For example: The sentence that you gave as an example is preterite, because it has a definite beginning and a definite end. (if that makes sense)

Hope that helped! :)