먹었다고

In a sentence

• 나는 밥을 다 먹었다고 말했다.

  I said that I finished eating.

  Here '먹었다고' is used to convey the act of having eaten as a reported statement.

• 그가 이미 점심을 먹었다고 들었어요.

  I heard that he already ate lunch.

  In this sentence, '먹었다고' reports the information received, showing past completion of eating.

• 선생님께서 학생들에게 음식을 다 먹었다고 하셨습니다.

  The teacher told the students that the food was finished eating.

  The use of '먹었다고' here indicates that the teacher informed others about the completion of eating.