diff --git a/Cargo.lock b/Cargo.lock
index 248ab62..ef296cf 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -104,7 +104,7 @@ checksum = "7f24254aa9a54b5c858eaee2f5bccdb46aaf0e486a595ed5fd8f86ba55232a70"
 
 [[package]]
 name = "http-request"
-version = "5.0.0"
+version = "5.1.0"
 dependencies = [
  "color-output",
  "hex",
diff --git a/Cargo.toml b/Cargo.toml
index 72613fa..dc2b2fa 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "http-request"
-version = "5.0.0"
+version = "5.1.0"
 edition = "2021"
 authors = ["ltpp-universe <root@ltpp.vip>"] 
 license = "MIT"
diff --git a/readme.md b/readme.md
index 384cb47..39a1078 100644
--- a/readme.md
+++ b/readme.md
@@ -37,8 +37,8 @@ cargo add http-request
 ```rs
 use http_request::*;
 use std::collections::HashMap;
-let mut header: HashMap<String, String> = HashMap::new();
-header.insert("header-key"., "header-value".);
+let mut header: HashMap<&str, &str> = HashMap::new();
+header.insert("header-key", "header-value");
 let mut _request_builder = HttpRequestBuilder::new()
     .get("https://ltpp.vip/")
     .headers(header)
@@ -64,10 +64,10 @@ _request_builder
 ```rs
 use http_request::*;
 use std::collections::HashMap;
-let mut header: HashMap<String, String> = HashMap::new();
-header.insert("header-key"., "header-value".);
-let mut body: HashMap<String, String> = HashMap::new();
-body.insert("body-key"., "body-value".);
+let mut header: HashMap<&str, &str> = HashMap::new();
+header.insert("header-key", "header-value");
+let mut body: HashMap<&str, &str> = HashMap::new();
+body.insert("body-key", "body-value");
 let mut _request_builder = HttpRequestBuilder::new()
     .post("http://localhost:80")
     .json(body)
@@ -92,8 +92,8 @@ _request_builder
 ```rs
 use http_request::*;
 use std::collections::HashMap;
-let mut header: HashMap<String, String> = HashMap::new();
-header.insert("header-key"., "header-value".);
+let mut header: HashMap<&str, &str> = HashMap::new();
+header.insert("header-key", "header-value");
 let mut _request_builder = HttpRequestBuilder::new()
     .post("http://localhost")
     .text("hello")