  "couldn't've": [{"F": "could", "pos": "MD"},
                  {"F": "n't", "L": "not", "pos": "RB"},
                  {"F": "'ve", "pos": "VB"}],
  "couldntve": [{"F": "could", "pos": "MD"},
                  {"F": "n't", "L": "not", "pos": "RB"},
                  {"F": "'ve", "pos": "VB"}],
  "Couldn't've": [{"F": "Could", "pos": "MD"},
                  {"F": "n't", "L": "not", "pos": "RB"},
                  {"F": "'ve", "pos": "VB"}],
  
  "didn't":  [{"F": "did", "pos": "VBD", "L": "do"},
 
</s> remove                 {"F": "n't", "L": "not", "pos": "RB"}],
 </s> add                 {"F": "nt", "L": "not", "pos": "RB"}], </s> remove                 {"F": "'ve", "L": "have", "pos": "VB"}],
 </s> add                 {"F": "ve", "L": "have", "pos": "VB"}], </s> remove             {"F": "n't", "L": "not", "pos": "RB"}],
 </s> add             {"F": "nt", "L": "not", "pos": "RB"}], </s> remove             {"F": "'d", "L": "would", "pos": "MD"},
            {"F": "'ve", "pos": "VB"}],
 </s> add             {"F": "d", "L": "would", "pos": "MD"},
            {"F": "ve", "pos": "VB"}], </s> remove             {"F": "n't", "L": "not", "pos": "RB"}],
 </s> add             {"F": "nt", "L": "not", "pos": "RB"}],
                {"F": "nt", "L": "not", "pos": "RB"},
                {"F": "ve", "pos": "VB"}],
  "couldn't've": [{"F": "could", "pos": "MD"},
                  {"F": "n't", "L": "not", "pos": "RB"},
                  {"F": "'ve", "pos": "VB"}],
  "couldntve": [{"F": "could", "pos": "MD"},
                {"F": "nt", "L": "not", "pos": "RB"},
                {"F": "ve", "pos": "VB"}],
                {"F": "nt", "L": "not", "pos": "RB"},
                {"F": "ve", "pos": "VB"}],
  "Couldn't've": [{"F": "Could", "pos": "MD"},
                  {"F": "n't", "L": "not", "pos": "RB"},
                  {"F": "'ve", "pos": "VB"}],
  
  "didn't":  [{"F": "did", "pos": "VBD", "L": "do"},
keep keep keep keep replace replace keep keep keep keep keep
 * Fix ... tokenization, and correct orth inconsistencies in specials.json 
lang_data/en/specials.json