Tutor profile: Emilia H.

What is the difference between the uses of "pretérito indefinido" and "pretérito imperfecto"?

In general, pretérito indefinido is used for concrete actions in the past, which had a short and specific duration (I know, the name "indefinido" does not help). For example, "ayer me caí por la calle" ("yesterday, I fell on the street"). On the other hand, pretérito imperfecto is used for actions which had duration in the past, or habits in the past. For example, "cuando era niña, siempre me caía por la calle" ("when I was a kid, I would always fall on the street"). You can use both in the same sentence: indefinido for the concrete action that you are describing, and imperfecto to provide the context of what was happening. For example: "Caminaba por la calle y me caí" ("I was walking down the street, and I fell").

What is the differece between using the expressions "because" and "because of"?

If you choose to use "because", you need a subject and a conjugated verb after it. For example: “Some people skip breakfast because they think it'll help them lose weight.” If you choose to use "because of", you need a noun or noun phrase after it. For example: “He needs to cut gluten out of his diet because of his gluten allergy.”

How do I use and form the future perfect tense?

Take a look at the following example. “If you stop using your car today, you will have reduced greenhouse gas emissions by 30% by 2025!” Pay attention to the second clause: "you will have reduced greenhouse gas emissions by 30% by 2025." This clause is written in the future perfect tense. When do we use the future perfect tense? We use future perfect to say something will be finished or completed before a certain time in the future. This tense is frequently used with the time expressions made up of “by” and a time expression, meaning “at the latest”; for example: “by Monday, June, 2025, etc. You could also use expressions with “in”, such as “in four weeks/ months”, etc or “in four weeks’ time”. How do we form future perfect? Let’s go back to the example we saw before: "You will have reduced greenhouse gas emissions by 30% by 2025" We form the future perfect tense using “will have” + the past participle of the verb, or the verb in the “third column”. If we want to make a negative sentence, we use “won’t have” + the past participle: "You won’t have reduced greenhouse gas emissions by 30% by 2025." If we want to ask a question, we just invert the subject and “will/won’t”. "Will you have reduced greenhouse gas emissions by 30% by 2025?"