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CC is used mainly to connect clauses to coordinating conjunctions. 

          +--S--+--MV--+-C-+-S-+      +-W---+--S--+
          |     |      |   |   |      |     |     |
     3.	John screamed when I arrived but   Sue   left 		

CC is used with coordinating conjunctions only, and it links
to the subject of the previous main clause. Subordinating
conjunctions, by contrast (like "when" and "after"), link to
the main verb of the previous clause, main or dependent. See
"W: Coordinating Conjunctions".

Another use of CC is in conditional constructions like this

      |                      |    |
      I would have seen you, had you been there                                     
      I would do it,        were it possible

Here, CCq is used. Instead of linking to the subject of the
following clause, the CCq links to a following auxiliary
(either "had" or "were"), which is then forced to use an
"SI*j+", creating subject-verb inversion.  Conditional
expressions can also be used as openers in this way: "Had you
been there, I would have seen you". For this, COp is used. For
this purpose, "had" and "were" have a special "SI*j+ & (CCq-
or COp+)" expression. 

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