The word 'sat' is the past tense of the verb 'sit'. This means it describes something that already happened. To 'sit' means to rest your body on a surface, usually using a chair or the ground. When you 'sat', it means you did this action before.
For example:
- Present tense: I sit on the chair.
- Past tense: Yesterday, I sat on the chair.
It’s like telling a story about what you did. If your teacher asks you where you were during class yesterday, you can say, 'I sat at my desk and listened.' This shows that you already did the action of sitting.