Definition: An inference is a guess that you get from evidence and information.
"Revenge…what does it really mean? It is fueled by uncontrollable anger just waiting to strike out. It can invoke terrible evils out of even the most good-hearted men."
An inference you could make about this writer is that he is against revenge. I based this on the fact that he/she says that revenge causes terrible evils.
"If a Nature special can be so inspiring and educational, are there any good arguments for keeping animals in artificial enclosures that, at best, are only a fraction of the size of their natural habitats?"
An inference you can make about this author is that she/he is against zoos. I based this on the fact that she/he speaks negatively about zoos.
A women is walking down the street pushing a stroller. An inference you could make is that she has a baby.
An inference you could make is that the kid is very good at math based on the fact that he is doing so much math.
An Inference you could make about this puppy is that he is tired based on the fact that he is lying on the ground.
An inference you could make about this dog is that he is happy based on the fact that he is eating a burger and dogs love food.