Update translation of 5-network/05-fetch-crossorigin (javascript-tutorial#724)

leviding · web-flow · commit ed382c29492e · 2020-04-10T15:13:04.000+08:00
diff --git a/5-network/05-fetch-crossorigin/1-do-we-need-origin/solution.md b/5-network/05-fetch-crossorigin/1-do-we-need-origin/solution.md
@@ -1,9 +1,9 @@
-We need `Origin`, because sometimes `Referer` is absent. For instance, when we `fetch` HTTP-page from HTTPS (access less secure from more secure), then there's no `Referer`.
+我们需要 `Origin`，是因为有时会没有 `Referer`。例如，当我们从 HTTPS（从高安全性访问低安全性）`fetch` HTTP 页面时，便没有 `Referer`。
 
-The [Content Security Policy](http://en.wikipedia.org/wiki/Content_Security_Policy) may forbid sending a `Referer`.
+[内容安全策略](http://en.wikipedia.org/wiki/Content_Security_Policy) 可能会禁止发送 `Referer`。
 
-As we'll see, `fetch` also has options that prevent sending the `Referer` and even allow to change it (within the same site).
+正如我们将看到的，`fetch` 也具有阻止发送 `Referer` 的选项，甚至允许修改它（在同一网站内）。
 
-By specification, `Referer` is an optional HTTP-header.
+根据规范，`Referer` 是一个可选的 HTTP-header。
 
-Exactly because `Referer` is unreliable, `Origin` was invented. The browser guarantees correct `Origin` for cross-origin requests.
+正是因为 `Referer` 不可靠，才发明了 `Origin`。浏览器保证跨源请求的正确 `Origin`。
diff --git a/5-network/05-fetch-crossorigin/1-do-we-need-origin/task.md b/5-network/05-fetch-crossorigin/1-do-we-need-origin/task.md
@@ -2,11 +2,11 @@ importance: 5
 
 ---
 
-# Why do we need Origin?
+# 我们为什么需要源（Origin）？
 
-As you probably know, there's HTTP-header `Referer`, that usually contains an url of the page which initiated a network request.
+你可能知道有一个 HTTP-header `Referer`，它通常包含发起网络请求的页面的 url。
 
-For instance, when fetching `http://google.com` from `http://javascript.info/some/url`, the headers look like this:
+例如，当从 `http://javascript.info/some/url` fetch `http://google.com` 时，header 看起来如下：
 
 ```
 Accept: */*
@@ -20,9 +20,9 @@ Referer: http://javascript.info/some/url
 */!*
 ```
 
-As you can see, both `Referer` and `Origin` are present.
+正如你所看到的，存在 `Referer` 和 `Origin`。
 
-The questions:
+问题是：
 
-1. Why `Origin` is needed, if `Referer` has even more information?
-2. If it possible that there's no `Referer` or `Origin`, or it's incorrect?
+1. 为什么需要 `Origin`，如果 `Referer` 甚至具有更多信息？
+2. 如果这里没有 `Referer` 或 `Origin` 可行吗，还是说会出问题？
diff --git a/5-network/05-fetch-crossorigin/article.md b/5-network/05-fetch-crossorigin/article.md
