tree_complementizer2tex

[S 
  [NP 
    [N' 
      [N John ] ] ] 
  [VP 
    [V knows ] 
    [CP 
      [C that ] 
      [S 
        [NP 
          [N' 
            [N I ] ] ] 
        [VP 
          [V love ] 
          [CP 
            [C when ] 
            [S 
              [NP 
                [N' 
                  [N you ] ] ] 
              [VP 
                [V hug ] 
                [NP 
                  [N' 
                    [N squirrels ] ] ] ] ] ] ] ] ] ] ]