turn in

To give work, or something you have found, to a person in authority.

• Please turn in your assignments by Friday.
  Lütfen ödevlerinizi Cuma gününe kadar teslim edin.
• She turned in the wallet she found to the police.
  Bulduğu cüzdanı polise teslim etti.

To go to bed.

• I'm tired, I think I'll turn in.
  Yorgunum, sanırım yatacağım.
• We turned in early because we had to catch a morning flight.
  Sabah uçağına yetişmemiz gerektiği için erken yattık.

To tell the police about someone, or take that person to the police.

• His own brother turned him in to the police.
  Onu polise kendi kardeşi ihbar etti.
• He turned himself in to the police the next morning.
  Ertesi sabah polise teslim oldu.