diff --git a/source/includes/intro-aggregation-boolean.rst b/source/includes/intro-aggregation-boolean.rst
index 976e9b0ca2f..6bc06667d1b 100644
--- a/source/includes/intro-aggregation-boolean.rst
+++ b/source/includes/intro-aggregation-boolean.rst
@@ -1,4 +1,4 @@
-Boolean expressions evaluates its argument expressions as booleans and
+Boolean expressions evaluate their argument expressions as booleans and
 return a boolean as the result.
 
 .. |boolean-exp| replace:: Boolean expression