What was the first man's lie to the king?

1. Yesterday, I killed a big dragon with my kick.
2. It was that yesterday, I killed a big dragon with my kick.
3. It was that the next day, he killed a big dragon with his kick.
-----------------------------------
Man 1 said like #1. Then, which answer is right, #2 or #3? #1 is a correct answer, isn't it?

I don't understand this.

If the question is a direct question to someone else, then is the "I" in #1 the answer that the someone else is giving to the person who asked the direct question?

Both 2 and 3 are phrased awkwardly. Once I understand the relationship between the question and #1, I might be able to help you with the others.

What was the first man's lie to the king?

1. Yesterday, I killed a big dragon with my kick.
2. It was that yesterday, I killed a big dragon with my kick.
3. It was that the day before, he killed a big dragon with his kick.
-----------------------------------
Man 1 said like #1. Then, which answer is right, #2 or #3? #1 is a correct answer, isn't it?

Based on the information given, the first man said that he killed a big dragon with his kick. The options given for the answer are:

1. Yesterday, I killed a big dragon with my kick.
2. It was that yesterday, I killed a big dragon with my kick.
3. It was that the next day, he killed a big dragon with his kick.

Since the first man's statement indicates that the dragon was killed "yesterday," it means that the event already happened in the past. Therefore, option #2, "It was that yesterday, I killed a big dragon with my kick," is the correct answer. Option #1 is not grammatically correct and does not match the tense used in the statement. Option #3 changes the pronoun from "I" to "he" and introduces the concept of the next day, which contradicts the original statement.