Fix typos in comments (GH-9905)

diff --git a/Modules/gcmodule.c b/Modules/gcmodule.c
index e3e290c..7cddaba 100644
--- a/Modules/gcmodule.c
+++ b/Modules/gcmodule.c
@@ -504,7 +504,7 @@
                     (void *)young);
             // relink gc_prev to prev element.
             _PyGCHead_SET_PREV(gc, prev);
-            // gc is not COLLECTING state aftere here.
+            // gc is not COLLECTING state after here.
             gc_clear_collecting(gc);
             prev = gc;
         }
diff --git a/Python/ceval.c b/Python/ceval.c
index 1a8c9e2..9a96dc7 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -3092,7 +3092,7 @@
                 /* There was an exception and a True return.
                  * We must manually unwind the EXCEPT_HANDLER block
                  * which was created when the exception was caught,
-                 * otherwise the stack will be in an inconsisten state.
+                 * otherwise the stack will be in an inconsistent state.
                  */
                 PyTryBlock *b = PyFrame_BlockPop(f);
                 assert(b->b_type == EXCEPT_HANDLER);
diff --git a/Python/pyarena.c b/Python/pyarena.c
index 103603f..abb5729 100644
--- a/Python/pyarena.c
+++ b/Python/pyarena.c
@@ -49,7 +49,7 @@
      */
     block *a_head;
 
-    /* Pointer to the block currently used for allocation.  It's
+    /* Pointer to the block currently used for allocation.  Its
        ab_next field should be NULL.  If it is not-null after a
        call to block_alloc(), it means a new block has been allocated
        and a_cur should be reset to point it.
@@ -57,7 +57,7 @@
     block *a_cur;
 
     /* A Python list object containing references to all the PyObject
-       pointers associated with this area.  They will be DECREFed
+       pointers associated with this arena.  They will be DECREFed
        when the arena is freed.
     */
     PyObject *a_objects;