diff --git a/chapter4.md b/chapter4.md
index e4210a7..a9e9cfe 100644
--- a/chapter4.md
+++ b/chapter4.md
@@ -256,7 +256,7 @@ fn main() -> Result<()> {
     loop {
         match handle_query(&socket) {
             Ok(_) => {},
-            Err(e) => eprintln!("An error occured: {}", e),
+            Err(e) => eprintln!("An error occurred: {}", e),
         }
     }
 }
diff --git a/examples/sample4.rs b/examples/sample4.rs
index eee856b..cc680de 100644
--- a/examples/sample4.rs
+++ b/examples/sample4.rs
@@ -794,7 +794,7 @@ fn main() -> Result<()> {
     loop {
         match handle_query(&socket) {
             Ok(_) => {},
-            Err(e) => eprintln!("An error occured: {}", e),
+            Err(e) => eprintln!("An error occurred: {}", e),
         }
     }
 }
diff --git a/examples/sample5.rs b/examples/sample5.rs
index 15abd8c..63268f8 100644
--- a/examples/sample5.rs
+++ b/examples/sample5.rs
@@ -887,7 +887,7 @@ fn main() -> Result<()> {
     loop {
         match handle_query(&socket) {
             Ok(_) => {},
-            Err(e) => eprintln!("An error occured: {}", e),
+            Err(e) => eprintln!("An error occurred: {}", e),
         }
     }
 }