Let's take a look at how to say "They say ...", "I hear that ...", or how to re-tell someone what you've heard from someone else. There are mainly two ways of saying this in Korean, and  we are going to learn how to use the endings -(ㄴ/는)대(요) and -(이)래(요) in this lesson.  These endings might sound complicated, but in fact, they are just combinations of the grammar points that you have already learned before.

In Level 5 Lesson 17, you learned the following grammar points:

-(ㄴ/는)다고
-(이)라고

These are used for quoting what someone has said and are also used with verbs related to speech. In that lesson, the following sample sentences were introduced:

뭐라고 했어요? = What did they say?
내일 온다고 했어요. = They said they would come tomorrow.
언제 온다고 했어요? = When did they say they would come?
이거 재미있다고 들었어요. = I heard that this is fun.

You can make all of the above sentences shorter by using the endings -(ㄴ/는)대(요) and -(이)래(요).

-(ㄴ/는)다고 해요 --> -(ㄴ/는)대요
-(이)라고 해요 --> -(이)래요

Although it's basically the same thing, the latter forms are more commonly used in everyday spoken Korean because they are shorter and much easier to pronounce.

Construction
[Present Tense]
Action Verbs + -(느)ㄴ대요
Ex) 지금 간대요. (= They say they are going now.)

Descriptive Verbs + -대요
Ex) 바쁘대요. (= He says that he's busy now.)

Nouns + -(이)래요
Ex) 친구래요. (= She says that he's a friend.)

[Past Tense]
Action Verbs + -았/었/였대요
Ex) 어제 만났대요. (= I heard they met yesterday.)

Descriptive Verbs + -았/었/였대요
Ex) 아팠대요. (= I heard she was sick.)

Nouns + -이었/였대요
Ex) 학생이었대요. (= They say they were students.)

[Future Tense]
Action Verbs + -(으)ㄹ 거 + 래요
Ex) 내일 만날 거래요. (= He says he will meet them tomorrow.)

Descriptive Verbs + -(으)ㄹ 거 + 래요
Ex) 추울 거래요. (= They say it will be cold.)

Nouns + -일 거 + 래요
Ex) 마지막일 거래요. (= They say it will be the last time.)

When you use the -(ㄴ/는)대요/-(이)래요 endings, you usually deliver a piece of information that the other person doesn't know, or that you think they don't know. If you want to emphasize the fact that YOU, at least, have heard something and it might not be the exact truth, you need to use verbs such as "듣다 (= to hear)" and say "-다고/라고 들었어요".

Sample Sentences
1. 이게 제일 좋대요.
[i-ge je-il jo-tae-yo.]
= They say that this is the best.

2. 여기 정말 유명하대요.
[yeo-gi jeong-mal yu-myeong-ha-dae-yo.]
= They say this place is really famous.

3. 몰랐대요.
[mol-lat-dae-yo.]
= He says he didn't know.

4. 벌써 다 끝났대요.
[beol-sseo da kkeut-nat-dae-yo.]
= They say it has ended already.

5. 어딘지 모른대요.
[eo-din-ji mo-reun-dae-yo.]
= He says he doesn't know where it is.

6. 이 사람 정말 유명한 사람이래요.
[i sa-ram jeong-mal yu-myeong-hal sa-ra-mi-rae-yo.]
= They say this person is a very famous person.

7. 친구가 내일 이사 간대요.
[chin-gu-ga nae-il i-sa gan-dae-yo.]
= My friend says she's moving tomorrow.

8. 제 친구가 한국에 올 거래요.
[je chin-gu-ga han-gu-ge ol geo-rae-yo.]
= My friend says he will come to Korea.

9. 그 사람은 한국에 와 본 적이 없대요.
[geu sa-ra-meun han-gu-ge wa bon jeo-gi eop-dae-yo.]
= He says he's never come to Korea.

10. 효진 씨는 어제도 집에 안 갔대요.
[hyo-jin ssi-neun eo-je-do ji-be an gat-dae-yo.]
= They say Hyojin, once again, didn't go home yesterday.