Okay to start off the more I read the more confusing signs and symbols were to me and then I had a breakthrough of a google search. A sign represents something and a symbols represents something based on association. So with the first example in the reading of an apple it could represent temptation(by association in religious paintings) but at the same time the word is a sign for the fruit of a tree that we eat. So that is about as close as I can get.
Verbal- Hot, can signifie a change in temperature or the attractiveness of some one.
Visual- Power, this sign signifies that when you contact this position and change it's state it will switch on what ever it is on.
Verbal- Pregnant, signifies that there probably was sex.
Visual- Wedding rings imply there was a wedding(this how ever is not always the case)
Verbal-Scream, although it isn't a common thing to write an audible scream symbolizes fear.
Visual- The double loop for infinityis used in physics to denote endless, then again it also hase no begining but lets not get into that.