I eat meat or fish every day, and I can not imagine what I willit would be like ifto only eat vegetables. I eat meat or fish every day, and I can not imagine what it would be like to only eat vegetables.

You can also say, "I can't imagine what it would be like if I only ate vegetables."👍

We know that true monks are not allowed to eat meat, because they can not kill living creatures. We know that true monks are not allowed to eat meat, because they can not kill living creatures.

I heard about a famous monk named Hai Deng who specialized in Kukongfu, and died in his Sseventies. I heard about a famous monk named Hai Deng who specialized in kongfu, and died in his seventies.

Because he was a martial art master and well-known in China, some doctors made a medical checkperformed an autopsy on his body in order to find the reason why he was not living as longevity as expected. Because he was a martial art master and well-known in China, some doctors performed an autopsy on his body in order to find the reason why he was not living as long as expected.

If you want to use the word 'longevity', you say also say "...in order to determine why his longevity didn't last."👍