I'm used to be a quite thin person when I was in high school, but I've gradually been getting heavy inier for years. I used to be quite thin when I was in high school, but I've gradually been getting heavier for years.

The "gradually" here helps express the idea that you started gaining weight as the years went by.

I'm used to be a quite thin person when I was in high school, but I've been getting heavy inier for years. I used to be quite thin when I was in high school, but I've been getting heavier for years.

I'm used to be a quite a thin person when I was in high school, but I've been getting heavy in forier during the past few years. I used to be a quite a thin person when I was in high school, but I've been getting heavier during the past few years.

I'm used to be a quite a thin person when I was in high school, but I've been getting heavy inier for years. I'm used to be quite a thin person when I was in high school, but I've been getting heavier for years.

I once played tennis atin the past, nowbut lately, my hobbies arehave been oil painting and making espresso, so I'm having fewer (coffee), so I've been getting less exercise. I once played tennis in the past, but lately, my hobbies have been oil painting and making espresso (coffee), so I've been getting less exercise.

I used "...I've been getting less exercise." here, but a shorter way would be "...I've been exercising less."

I played tennis at the past, but now my hobbies are oil painting and espresso, so I'm having fewer exercise less. I played tennis at the past, but now my hobbies are oil painting and espresso, so I exercise less.

I played tennis atin the past, and now my hobbies are oil painting and drinking espresso, so I'm having fewerless exercise. I played tennis in the past and now my hobbies are oil painting and drinking espresso, so I'm having less exercise.

I played tennis atin the past, and now my hobbies are oil painting and espresso, so I'm having fewergetting less exercise. I played tennis in the past and now my hobbies are oil painting and espresso, so I'm getting less exercise.

I'm not that interested in my body shape if I am in the healthy range. I'm not that interested in my body shape if I am in the healthy range.

I'm not that interested inconcerned about my body shape ifas long as I am in a healthy range. I'm not that concerned about my body shape as long as I am in a healthy range.

I'm not that interested in my body shape ifas long as I am in a healthy range. I'm not that interested in my body shape as long as I am in a healthy range.