4. Ability to use the 
      mechanics of the language.  
       
      Language is used properly including: 
      • Grammar and usage, e.g.,  
      - subject-verb agreement  
      - pronoun references (all pronouns refer 
      to definite nouns) 
       
      • Punctuation 
      - Commas are used to:  
      * signal nonrestrictive or nonessential  
      material,  
      * prevent confusion, and  
      * indicate relationships among ideas 
      and sentence parts.  
       
      - Unnecessary commas that make 
      sentences difficult to read are absent.  
       
      - Two independent clauses are linked 
      with a comma when used with a 
      coordinating conjunction: ("and," "or,"
      "but," "for," "nor," "so," "yet"). Other-wise, a period or semi-colon is used. 
       
      - Apostrophes indicate possession for 
      nouns ("Jeanne's hat," "several years' 
      work") but not for personal pronouns 
      ("its," "your," "their," and "whose").  
      Apostrophes also indicate omissions in 
      contractions ("it's" = "it is"). In general 
      they are not used to indicate plurals. 
       
      • Spelling 
       
      • Capitalization | 
      
      
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