diff --git a/src/pkg/crypto/cipher/example_test.go b/src/pkg/crypto/cipher/example_test.go
index 373f6791be..5677f6f2fe 100644
--- a/src/pkg/crypto/cipher/example_test.go
+++ b/src/pkg/crypto/cipher/example_test.go
@@ -240,7 +240,7 @@ func ExampleStreamReader() {
 	}
 
 	// Note that this example is simplistic in that it omits any
-	// authentication of the encrypted data. It you were actually to use
+	// authentication of the encrypted data. If you were actually to use
 	// StreamReader in this manner, an attacker could flip arbitrary bits in
 	// the output.
 }