Day 4: Why I am not happy?

I studied English hard this week and had a long day/week.
I don't was not  happy with during that. Why?
The reason why is, "Learning a foreign language is just a tools." I forgot it./I failed to recognize it.  that things.

I went to a happy hour event at the school/institute where I'm joining/(going to go) to next Monday./ ( where I will be joining from next Monday)
I met future classmates, one of them is from new York.
He speaks (His speaking is) very fast, but he and I are of the same age and take a common class,
so I could talk with him about design.
When I went to an English language school, I couldn't speak not (double negation is not allowed in English) at all. I even realized that I don't/(couldn't) speak well even Japanese well.
Having a common talking point is important/essential in initiating to the a conversation./(Having a commonality is important/essential in a conversation.)
I know/knew that, but I forgot that  it completely.
At the night, I was very happy. I've not don't forgotten the experience.

頑張ってください。

Day 4: Why I am not happy?

I studied English hard this week and had a long day.
I wasn't happy during that. Why?
The reason why is learning a foreign language is just tools. I forgot that things. (editor's note: I'm confused on meaning here)

I went to a happy hour event at the school where I'm going to go to next Monday.
I met future classmates; one of them is from New York.
His speaking is very fast, but he and I are the same age and take a common class,
so I could talk with him about design.
When I went to an English language school, I couldn't speak not at all. I realized I don't speak well, even in Japanese.
Having a common point is important to the conversation.
I know that, but I forgot that completely.
At the end of the night, I was very happy. I haven't forgotten the experience.