A test on corrections of English usage

I have done a test on corrections of English usage. The test is to correct errors for the sentences enclosed by two ". The criteria are retaining the original meaning and words as much as possible and that any unnecessary changes may be penalized.
I have done the following changes:
As a demonstration, 1.) has a suggested answer given by the test paper so I didn't do it.
2.) I enjoyed to live aboard.
2.) I enjoyed living abroad.
3.) Now, when I look back, I think those were the most happiest daysof my live.

3.) Now when I look back, I think those are the happiest days in mylife.
4.) It was so heat in Dubai so we had to take great care in the son.
4.) It was so hot in Dubai that we had to take great care of the son.
5.) school we had to rush to home to have a shower cool down.
5.) school we had to rush home to have a shower for cooling.
6.) my father was banker so our house were always full of importantpeople.

6.) my father was a banker so our house was always full of importantpeople.
7.) Too many of them were politicians and bankers which meant that thedinner conservation

7.) Very many of them were politicians and bankers and that means theconservation at dinner
8.) Although I was only a boy, but I still remember every thing veryclear.

8.) Although I was only a boy, I still remember everything veryclearly.
9.) sand was bright red like it was in fire.
9.) sand was bright red like that it was on fire.
10.) It was a pleasure and excited ride!
10.) It was a pleasant and exciting ride!
11.) I visited Dubai once since I left it has changed so much.
11.) I have visited Dubai once again. It has changed so much since Ileft.
I am not sure about 11.) as I don't quite get what the writer wanted to say.
So do you think I have done the corrections properly, or should I change some of them with better answers? Thanks in advance.
David
Living in another country
1) "When I am young I lived in another country for seven year." Ilived in Dubai which is in the Middle East when my father was working as a banker there. 2) "I enjoyed to live aboard." 3) "Now, when I look back, I think those were the most happiest days of my live."4) "It was so heat in Dubai so we had to take great care in the son."I remember wearing a hat all the time to protect me of the bright rays. The weather was cooler in the evenings and early mornings. 5) Every day after "school we had to rush to home to have a shower cool down." It was an interesting place to grow up. I made many friends in Dubai and we still keep in touch today.

6) As I mentioned earlier, "my father was banker so our house were always full of important people." I liked it when he had dinner parties because I could met many different people. 7) "Too many of them were politicians and bankers which meant that the dinner conservation" was always serious! 8) "Although I was only a boy, but I still remember every thing very clear."
9) My mother was very kind and she used to take me into the desert forpicnics. 9) The "sand was bright red like it was in fire." I liked to play with the camels and once I rode a camel for an hour. 10) "It was a pleasure and excited ride!"
Now I am older and I am living in the USA again. 11) "I visited Dubai once since I left it has changed so much." I think that living in a foreign country as a child made me appreciate other cultures more. I still like traveling and I hope that one day I might get to live in another country for a longer time.