Answer:
There are many way sims die in the sims 3....
1. old age- they just grow old and die
2. fire- leave food cooking on a bad stove and it catches fire, if there are no fire alarms and no one calls 911 the sim can catch on fire and die.
3. drowning- if you build a wall around the pool the sim can't get out and will drown.
4.starvation- if you keep the sim away from food it will grow to hungry and die.
5.electrocution- If you make a sim tinker with something electric (tvs, radios,etc.) they might get unlucky and by electrocuted to death.
Well there are all the ones i know of, but see if you can find out more!!
(Btw who ever wrote the last answer lied! (They were thinking of sims 2)
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