diff --git a/wacc-syntax/syntaxes/wacc.tmLanguage.json b/wacc-syntax/syntaxes/wacc.tmLanguage.json
index 775dc30..6093503 100644
--- a/wacc-syntax/syntaxes/wacc.tmLanguage.json
+++ b/wacc-syntax/syntaxes/wacc.tmLanguage.json
@@ -23,7 +23,7 @@
 			"name": "keyword.other.unit"
 		},
 		{
-			"match": "\\b(if|then|else|fi|while|do|done|skip)\\b",
+			"match": "\\b(if|then|else|fi|while|do|done|skip|is)\\b",
 			"name": "keyword.control.wacc"
 		},
 		{