chore(i18n,curriculum): update translations (#42684)

curriculum/challenges/chinese/02-javascript-algorithms-and-data-structures/basic-javascript/concatenating-strings-with-the-plus-equals-operator.md

@@ -20,7 +20,7 @@ var ourStr = "I come first. ";
 ourStr += "I come second.";
 ```
 
-`ourStr` 现在内容为字符串 `I come first. I come second.`
+`ourStr` 的值为字符串 `I come first. I come second.`
 
 # --instructions--
 
@@ -28,7 +28,7 @@ ourStr += "I come second.";
 
 # --hints--
 
-`myStr` 的值应该是 `This is the first sentence. This is the second sentence.`
+`myStr` 的值应该是字符串 `This is the first sentence. This is the second sentence.`
 
 ```js
 assert(myStr === 'This is the first sentence. This is the second sentence.');

curriculum/challenges/chinese/02-javascript-algorithms-and-data-structures/basic-javascript/use-the-conditional-ternary-operator.md

@@ -10,7 +10,7 @@ dashedName: use-the-conditional-ternary-operator
 
 条件运算符（ <dfn>conditional operator</dfn>,）（也称为三元运算符（ <dfn>ternary operator</dfn>））的就像写成一行的 if-else 表达式
 
-语法是 `a ？ b: c`，其中 `a` 是条件，`b` 是条件返回 `true` 时要运行的代码，`c` 是条件返回 `false` 时要运行的代码。
+语法是：`a ? b : c`, where `a` 是条件，当条件返回 `true` 的时候运行代码 `b`，当条件返回 `false` 的时候运行代码 `c`。
 
 以下函数使用 `if/else` 语句来检查条件：