Learn by looking at others do something
        
             
        
        
        
Chemicals from sea slugs may be useful in <span>sewage treatment plants.
</span>The sewage treatment plants process includes <span> removing contaminants from wastewater, primarily from household sewage. </span>
The output of the sewage treatment process is treated wastewater that is safer for the environment.
        
                    
             
        
        
        
1) Communicationlanguage allows one to understand the thoughts of another2) Arbitrariness<span>Relation between a word and what it refers to is arbitrary
</span>3) Meaningful structure<span>All languages are patterned so larger structures build in a sensible way on smaller ones
hope this helps!!!
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