2 files changed, 78 insertions, 1 deletions
diff --git a/chapter03/docs/03-grammar.ja.md b/chapter03/docs/03-grammar.ja.md
new file mode 100644
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@@ -0,0 +1,75 @@
+# 第3章の文法
+
+[English](03-grammar.md) | 日本語
+
+この文書は [原文](03-grammar.md) の日本語訳です。
+
+
+[第3章に戻る](../README.ja.md)
+
+```antlrv4
+grammar SimpleLanguage;
+
+program
+    : statement+ EOF
+    ;
+
+statement
+    : returnStatement
+    | declStatement
+    | blockStatment
+    | expressionStatement
+    ;
+
+
+expressionStatement
+    : IDENTIFIER '=' expression ';'
+    ;
+
+blockStatement
+    : '{' statement+ '}'
+    ;
+
+declStatement
+    : 'int' IDENTIFIER '=' expression ';'
+    ;
+
+returnStatement
+    : 'return' expression ';'
+    ;
+
+expression
+    : additiveExpression
+    ;
+
+additiveExpression
+    : multiplicativeExpression (('+' | '-') multiplicativeExpression)*
+    ;
+
+multiplicativeExpression
+    : unaryExpression (('*' | '/') unaryExpression)*
+    ;
+
+unaryExpression
+    : ('-') unaryExpression
+    | primaryExpression
+    ;
+
+primaryExpression
+    : IDENTIFIER
+    | INTEGER_LITERAL
+    | '(' expression ')'
+    ;
+
+INTEGER_LITERAL
+    : [1-9][0-9]*
+    | [0]
+    ;
+
+IDENTIFIER
+    : NON_DIGIT (NON_DIGIT | DIGIT)*
+    ;
+
+NON_DIGIT: [a-zA-Z_];
+DEC_DIGIT: [0-9];
+```
diff --git a/chapter03/docs/03-grammar.md b/chapter03/docs/03-grammar.md
index 1d36b532..3ae8463e 100644
--- a/chapter03/docs/03-grammar.md
+++ b/chapter03/docs/03-grammar.md
@@ -1,4 +1,6 @@
-# Grammar for Chapter 1
+# Grammar for Chapter 3
+
+English | [日本語](03-grammar.ja.md)
 
 ```antlrv4
 grammar SimpleLanguage;