An inference is "a conclusion reached on the basis of evidence and reasoning." For example, if the lights in somebody's house are not turned on, one can infer that nobody is home.
Because of the face this kid is making, I can infer that he does not like the food thatis on his plate.
Based on the color of this person's feet, I can infer that they stayed in the sun for too long. I can also infer that this person was wearing flip flops during the time they got burned because of the tan lines. Lastly, I can predict that it is summer outside because the sun is out most during summer.
Because of their positions, I can infer that they just lost their game.
"'Yeah, so much fun..." I mumble, feeling uncomfortable, shifting my weight from my left foot to my right foot."
Because this person is shifting their weight from their left foot to their right, I can infer and visualize that they feel/ look nervous.