diff --git a/ch04_keys.adoc b/ch04_keys.adoc
index 9ec33000..eccdbabe 100644
--- a/ch04_keys.adoc
+++ b/ch04_keys.adoc
@@ -1034,7 +1034,7 @@ designed to use this mechanism, allowing users to
 immediately begin accessing many of the new benefits by using a P2SH
 address.  But for Bob to gain access to all of the benefits, he would
 need Alice's wallet to pay him using a different type of script.  That
-would require Alice's wallet to upgrade to supporting the new scripts.
+would require Alice's wallet to upgrade to support the new scripts.
 
 At first, Bitcoin developers proposed BIP142, which would continue using
 base58check with a new version byte, similar to the P2SH upgrade.  But