I don't like doing everything. Because, I'm tired. I worked to 09:00 - 21:00. So, When i go to home, I'm tired.  

--> I don't like doing everything because, I'm tired. I work from 09:00 to 21:00. So, When I got home, I'm already tired. 

​-나는 그가 다른 여자와 데이트하는 장면을 목격했다.

- I saw him had date with another girl. ✔​

=> Another way: Your sentence is okay and this is another way of saying it.

I caught sight of him dating another girl. 

-나는 무릎을 꿇고 용서를 구했다.

-I ask for forgiveness on my knees. ✔​

=> Another way: Your sentence is okay and this is another way of saying it.​

I fell to my knees and begged forgiveness. 

-자동차 판매량이 5% 이상 줄어 들었다.

- Car sales volume had down 5% or more. --> Car sales dropped more than five percent.

=> Corrected : The sentence is corrected grammatically.

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