Notes1：U can call students that at their first year in college "freshman", means curious about almost every new things, and second year "sophomore", means that they know more than their first year, and third year "junior", means they understand some low level professional knowledge, and fourth year "senior", means they have grown up and can deal with problems with their major subjects.
Notes2: When you are watching somebody, U can mostly see their postures. When they are not moving, being static. Maybe they are standing quitely,sitting on the chair to rest, they may have a full squat or a partial squat, they may be in lying position on the bed, they may be kneeling due to their doing something wrong, they will crouch in the corner of the room when they feel sad, the children who cannot walk may All-fours on the ground.