A mouth morpheme changes the meaning of the sign even the sign looks exactly the same.

Sign 1
best
​sure, good

Sign 2
wrong
unexpected
accident, mishap

Sign 3
awful 
impossible
interesting, didn’t realize that

Sign 4
Sick
far out, funny 
huh 
silly, funny 

Sign 5
aww 
heartfelt
feel bad, wrenching 

Sign 6
anxious, nervous 
uncertain
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