I had the first time done some housework when I was 7 years

不符合语法,正确的说法：
I was only seven years old when I did housework for the first time .

祝你开心.

My first experience of doing housework came when I was only seven years old.
或者：I tried to do housework for the first time when I was only seven years old.

By the time I was seven, I had already had my first experience of doing housework.

希望对你有帮助

had+done 这是过去完成时。。。这个时态比较奇怪 如果想说强调的是“才” 应该写成：
It was only 7 years old when I did my housework for the first time.
这种强调句型比较好 但是从语法上来说没有错误 只是句子不甚漂亮 没有将中文完整反映
如果这次做家务对现在无影响 可用had 有影响hav...