diff --git a/runtime/syntax/php.yaml b/runtime/syntax/php.yaml
index bd0c5395..b3f2dc4b 100644
--- a/runtime/syntax/php.yaml
+++ b/runtime/syntax/php.yaml
@@ -18,7 +18,7 @@ rules:
     - comment: "<!--.+?-->"
     - default: "<\\?(php|=)\" end=\"\\?>"
     - identifier.class: "([a-zA-Z0-9_-]+)\\("
-    - preproc: "(require|include|require_once|include_once)"
+    - preproc: "\\b(require|include)(_once)?)\\b"
     - type: "\\b(var|class|extends|function|echo|case|default|exit|switch|extends|as|define|do|declare|in|trait|interface|[E|e]xception|array|int|string|bool|iterable|void)\\b"
     - identifier.class: "[a-zA-Z\\\\]+::"
     - identifier: "([A-Z][a-zA-Z0-9_]+)\\s"