Hi Kris! Thanks for correcting my article.

First, let's look at your sentence structure. A simple sentence is a complete unit of thought that ends with a period. A complex or compound sentence has a few units of thought connected together. Let's first take your writing and make it into units of thought:

Today, my brother told me that he got mad at his colleague a few days ago.

It was a misunderstanding.

"How did you know?" I asked.

He said, "Because I wasn't clear about his situation when I yelled at him."

After my brother knew about everything, he made an apology to his colleague.

I think he is doing a good job daring to admit mistakes.

I believe it important to focus on sentences when you are writing English, and to try to keep them simple. The more you try to combine them, the more chances that you will make grammar or punctuation errors.

Second, there are two phrasal verbs in your article: mad at and yelled at. As you know, there are many of these verb-preposition phrases in English (as well as in Chinese: 想到，跑上，吞下). So when you are learning a verb, you should also learn the prepositions that go with them:

come up, come off

shoot down, shoot up

sit down, sit up

etc., etc.

Dares to admit mistakes

Today, my brother told me that he got mad at his colleague few days ago and that was a misunderstanding, how did you know?, I asked. He said, because I didn't get his situation clearly then yelled him. After my brother knew about everything, he made a apology to his colleague. I think he is doing a good job about dares to admit mistakes.