Minor typo fixes in doc/warning

doc/library/sparse/index.txt

@@ -124,7 +124,7 @@ List of Implemented Operations
     - :func:`csr_from_dense <theano.sparse.basic.csr_from_dense>`,
       :func:`csc_from_dense <theano.sparse.basic.csc_from_dense>`.
       The grad implemented is structured.
-    - Theano SparseVariable object have a method ``toarray()`` that is the same as
+    - Theano SparseVariable objects have a method ``toarray()`` that is the same as
       :func:`dense_from_sparse <theano.sparse.basic.dense_from_sparse>`.
 
 - Construction of Sparses and their Properties

doc/library/typed_list.txt

@@ -22,7 +22,7 @@ the same Theano type. Here is an example::
 
 A second example with Scan. Scan doesn't yet have direct support of
 TypedList, so you can only use it as non_sequences (not in sequences or
-as outputs).::
+as outputs)::
 
     import theano.typed_list
 

theano/tensor/signal/conv.py

@@ -88,7 +88,7 @@ def conv2d(input, filters, image_shape=None, filter_shape=None,
     if input.ndim == 2 and filters.ndim == 2:
         if theano.config.warn.signal_conv2d_interface:
             warnings.warn(
-                "theano.tensor.signal.conv2d() now output 2d tensor when both"
+                "theano.tensor.signal.conv2d() now outputs a 2d tensor when both"
                 " inputs are 2d. To disable this warning, set the Theano flag"
                 " warn.signal_conv2d_interface to False",
                 stacklevel=3)