diff --git a/src/building/how-to-build-and-run.md b/src/building/how-to-build-and-run.md
index 8f6f860b..63bc7396 100644
--- a/src/building/how-to-build-and-run.md
+++ b/src/building/how-to-build-and-run.md
@@ -125,7 +125,7 @@ means the following command:
 ./x check
 ```
 
-could been replaced by:
+could be replaced by:
 
 ```bash
 ./x.py check