Contrast between verb tenses

Verb tenses:- Past Simple - Present Perfect Simple - Past Perfect Simple

Past Simple

• To express past actions, in general. For example: I ate an apple.
• To talk about actions that happened at a specific time in the past. For that, we use adverbs of time such as yesterday, last month, a year ago... For example: I played tennis a month ago with my friends.
• To express past actions that took place consecutively. For example: Yesterday morning, I woke up, had breakfast and went to school.
• To tell how things were in the past. For instance: 200 years ago, cars didn't exist.

Present Perfect Simple

• To express actions that started in the past but still continue in the present. We normally use for and since. For example: I have worked here for ten years (empecé a trabajar en 2011 pero sigo trabajando actualmente en el mismo lugar).
• To talk about actions that started in the past but still affect or have consecuences in the present. In addition, we do not mention when they happened. For instance: I have bought a new house. I live there now.
• Very recent actions. We normally add just. For example: I have just finished my homework.

Past Perfect Simple and Past Simple

• To emphasize the result of an action or activity in the past. For example: I got a job in London. For that reason, I had been in that city twice.
• Normally, it is used with the Past Simple (y así lo tenemos que estudiar nosotros). The action that goes in Past Perfect Simple took place BEFORE another, which is in Past Simple. For instance: I had met Tom before we became friends.

Present Perfect Simple and Past Simple

• As we have already studied, Present Perfect Simple is used when we are expressing that an action began in the past but it still affects the present, without making reference to the time when it happened.
• On the other hand, we use Past Simple to focus on the time on which the action took place in the past. This action finished in the time mentioned.

Look at the following examples: He has lived in Paris since 2003 vs. He lived in Paris a year ago.