diff --git a/spec.html b/spec.html
index 6967906..7290565 100644
--- a/spec.html
+++ b/spec.html
@@ -6016,7 +6016,7 @@ <h2>Acknowledgments</h2>
       </p>
       <p>MathML Core was initially developed by the MathML Community Group, and
 	then by the Math Working Group. Working Group or Community Group
-	members who regularly participated to MathML
+	members who regularly participated in MathML
         Core meetings during the development of this specification:
         Brian Kardell,
         Bruce Miller,