1. She's always been very sensible about how she
spends her money. That's why she can afford to retire
 at 55.
2. Pepito's put on a lot of weight recently. Don't say
anything to him though. He's very sensitive about it.
3. He acts like a tough guy, but I find him to be a very
sensitive and caring human being.
4. I don't think it's very sensible to go out without a
coat on this weather. It's freezing outside!

Sensible = "sensato", "prudente"
Sensitive = "sensible"