A/V(으)ㄹ 거예요 ②

Supposition

Structure
Vowel-final: 가다 → 가 + ㄹ 거예요 → 갈 거예요 (will go)
Consonant-final: 먹다 → 먹 + 을 거예요 → 먹을 거예요 (will eat)
ㄹ-final: 살다 → 살 + 거예요 → 살 거예요 (will live)
Explanation

-(으)ㄹ 거예요 expresses the speaker's supposition based on a personal experience or something seen or heard that provides a basis for the belief.

It corresponds to 'think' or 'will' in English.

When the verb or adjective stem ends in a vowel or ㄹ, -ㄹ 거예요 is used, and when the stem ends in a consonant, -을 거예요 is used.

In the case of past tense supposition, -았/었 is added in front of -(으)ㄹ 거예요 to form -았/었을 거예요.

Details

When used to indicate supposition, -을 거예요 cannot be used in questions. For question -(으)ㄹ까요? is used.

가: 내가 이 옷을 입으면 멋있을까요? (이 옷을 입으면 멋있을 거예요? ✕)
A: Do you think these clothes will look good on me?
나: 네, 멋있을 거예요.
B: Yes, I think you'll look nice in them.

Kimchi Reader

Expresses the speaker's supposition about a certain situation based on something heard, seen or personal experience.