Why does everything appear in the list?

[bom04]

Hi.
Even if it's awkward by turning the translator, please understand.
Like the picture below, all the contents of the article are shown in the list.

But all I want is to see the first line of text. like this.

If the text is long, I want to make it visible by clicking 'Read More'.
The code below is my code.

---
layout: post
title: "git 정리1"
tags: [git]
comments: true
---

저장소 종류, 커밋 히스토리, 되돌리기, non-fast-forward 

---

### 저장소 종류

I hope you can help.
thank you.

[bom04]

solve. I use this.
excerpt_separator