더 자연스러운 버전으로 고칠게요. 별써 고치셨던 분이 그냥 틀린 점을 고쳐서 글은 별로 자연스럽지 않고, 조금 외국인스러운 것 같아요.

New World [제목은 항상 capital로 해야 돼요.]

Today's friday, and I'm a lot happier than yesterday when I went to see the dentist. He said some of my teeth were rotten. [or 'some of my teeth had cavities'] Haha oops [조금 옛날의 표현인데, 여기서 쓰면 얄미운 느낌이 들어서 적당한 것 같아요.]

Seeing the dentist is always scary for me because he cover my eyes with a towel. I'm afraid of the dark, and because of the towel I can't see what's happening, so the noises of all the machines freak me out.

The thought of the [any] dental clinic makes me feel terrible. Just thinking about it makes me feel sick.

English is difficult ㅠㅠ [그래요? 전 별로 안 어려운데요. ^^]

new world

Today is friday.

I was happier than yesterday before until I went to see a dentist.

He said some of my teeth was rotten...

oops

Seeing a dentist is always scary to me, 

because he covers my eyes with a towel and I open my mouth.

I feel fear of the dark and hear the noise of machinery noise.

The thought of a dental clinic makes me feel terrible, 

so now my mood is so so.

English is difficult ㅠㅠ