@anaid99,
I've never heard a silly person referred to as a sausage, i doubt that it's an American expression.
An apple-polisher is someone who fawns over, who flatters someone in a position of power, hoping to gain favor thereby.
In rural areas of America, especially in the South, Sugar is a form of affectionate address from a person of one gender to someone of the opposite gender--it is sometimes verbally abbreviated to "Shoog."
Wiener
is used in the United States for a stupid, or dull-witted person. A wiener is a sausage, but i've never head an American use sausage that way. Another name for a wiener or frankfurter is "hot dog," hot dog is also used to refer to someone who is good at something and likes to show off by doing it.
A common breakfast food is toasted bread, usually just called toast. Figuratively if
something is said to be toast, it means that it has been destroyed or is about to be destroyed, or has been so badly damaged that it no longer functions. If you say
someone is toast, it means that they are in really big trouble.
If i think of any more, i'll try to remember to drop them off here.