diff --git a/assert/mod.ts b/assert/mod.ts
index ddfa2253c88c..00835ef78b60 100644
--- a/assert/mod.ts
+++ b/assert/mod.ts
@@ -3,7 +3,7 @@
 
 /** A library of assertion functions.
  * If the assertion is false an `AssertionError` will be thrown which will
- * result in pretty-printed diff of failing assertion.
+ * result in pretty-printed diff of the failing assertion.
  *
  * This module is browser compatible, but do not rely on good formatting of
  * values for AssertionError messages in browsers.