Typo fixes

doc/tutorial/faq.txt

@@ -6,7 +6,7 @@ Frequently Asked Questions
 ==========================
 
 TypeError: object of type 'TensorVariable' has no len()
---------------------------------------------------------------
+-------------------------------------------------------
 
 If you receive this error:
 
@@ -14,10 +14,10 @@ If you receive this error:
 
    TypeError: object of type 'TensorVariable' has no len()
 
-We can't implement the __len__ function on Theano Varible. This is
-because Python request that we return an integer, but we can't do this
-as we are working with symbolic variable. You can use `var.shape[0]`
-as a workaround.
+We can't implement the __len__ function on Theano Variables. This is
+because Python requires that this function returns an integer, but we
+can't do this as we are working with symbolic variables. You can use
+`var.shape[0]` as a workaround.
 
-Also we can't change the error to a better one for some other Python
-internal behavior that we can't change.
+Also we can't change the above error message into a more explicit one
+because of some other Python internal behavior that can't be modified.