Typo fixes

theano/compile/function.py

@@ -145,7 +145,7 @@ def function(inputs, outputs=None, mode=None, updates=None, givens=None,
                the cvm is a linker that replaces this python loop with a c
                loop to avoid continuously changing between python and c.
                The CVM is faster for 2 reasons:
-                 1) It's internal logic in C, so no Python interpreter overhead.
+                 1) Its internal logic in C, so no Python interpreter overhead.
                  2) It makes native calls from the VM logic into thunks that
                  have been compiled using the CLinker.
                the vm is a linker that was developed to prototype the cvm. it

theano/gof/graph.py

@@ -239,13 +239,13 @@ class Variable(utils.object2):
     - `Constant` (a subclass) which adds a default and un-replaceable :literal:`value`, and
       requires that owner is None
 
-    - `TensorVariable` subclass of Variable that represent numpy.ndarray object
+    - `TensorVariable` subclass of Variable that represents a numpy.ndarray object
 
     - `SharedTensorVariable` Shared version of TensorVariable
 
-    - `SparseVariable` subclass of Variable that represent scipy.sparse.{csc,csr}_matrix object
+    - `SparseVariable` subclass of Variable that represents a scipy.sparse.{csc,csr}_matrix object
 
-    - `CudaNdarrayVariable` subclass of Variable that represent our object on the GPU that is a subset of numpy.ndarray
+    - `CudaNdarrayVariable` subclass of Variable that represents our object on the GPU that is a subset of numpy.ndarray
 
     - `RandomVariable`