diff --git a/dlls/kernel32/tests/sync.c b/dlls/kernel32/tests/sync.c
index b01498b..06b1e5c 100644
--- a/dlls/kernel32/tests/sync.c
+++ b/dlls/kernel32/tests/sync.c
@@ -549,7 +549,7 @@
     HANDLE e;
     BOOL ret;
 
-    /* Test asyncronous deletion of the queue.  */
+    /* Test asynchronous deletion of the queue. */
     q = CreateTimerQueue();
     todo_wine
     ok(q != NULL, "CreateTimerQueue\n");
@@ -560,7 +560,7 @@
     todo_wine
     ok(GetLastError() == ERROR_IO_PENDING, "DeleteTimerQueueEx\n");
 
-    /* Test syncronous deletion of the queue and running timers.  */
+    /* Test synchronous deletion of the queue and running timers. */
     q = CreateTimerQueue();
     todo_wine
     ok(q != NULL, "CreateTimerQueue\n");
@@ -614,7 +614,7 @@
     todo_wine
     ok(n5 == 1, "Timer callback 5\n");
 
-    /* Test syncronous deletion of the queue with event trigger.  */
+    /* Test synchronous deletion of the queue with event trigger. */
     e = CreateEvent(NULL, TRUE, FALSE, NULL);
     if (!e)
     {
diff --git a/dlls/quartz/avisplit.c b/dlls/quartz/avisplit.c
index 2bbd8f1..ed9d3f1 100644
--- a/dlls/quartz/avisplit.c
+++ b/dlls/quartz/avisplit.c
@@ -20,7 +20,7 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  */
 /* FIXME:
- * - Reference leaks, if they are still existant
+ * - Reference leaks, if they still exist
  * - Files without an index are not handled correctly yet.
  * - When stopping/starting, a sample is lost. This should be compensated by
  *   keeping track of previous index/position.
@@ -410,7 +410,7 @@
         stream->pos_next = stream->pos;
         stream->index_next = stream->index;
 
-        /* There should be a a packet queued from AVISplitter_next_request last time
+        /* There should be a packet queued from AVISplitter_next_request last time
          * It needs to be done now because this is the only way to ensure that every
          * stream will have at least 1 packet processed
          * If this is done after the threads start it could go all awkward and we
diff --git a/dlls/quartz/tests/avisplitter.c b/dlls/quartz/tests/avisplitter.c
index d3cdaac..a7461f4 100644
--- a/dlls/quartz/tests/avisplitter.c
+++ b/dlls/quartz/tests/avisplitter.c
@@ -177,7 +177,7 @@
 /* This test doesn't use the quartz filtergraph because it makes it impossible
  * to be certain that a thread is really one owned by the avi splitter
  * A lot of the decoder filters will also have their own thread, and windows'
- * filtergraph has a seperate thread for start/stop/seeking requests.
+ * filtergraph has a separate thread for start/stop/seeking requests.
  * By avoiding the filtergraph all together and connecting streams directly to
  * the null renderer I am sure that this is not the case here.
  */