takaisin

In a sentence

• Haluan mennä takaisin kotiin.

  I want to go back home.

  In this sentence, 'takaisin' means 'back' and is used to indicate returning to a previous place, in this case, 'home'.

• Annatko kirjan takaisin?

  Will you give the book back?

  Here, 'takaisin' means 'back' as in returning an item, specifically the book, to its previous owner or place.

• Löysin avaimet takaisin auton vierestä.

  I found the keys back beside the car.

  In this case, 'takaisin' is used to indicate the location where something was re-found or revisited, implying a return to a known situation or circumstance.