diff --git a/src/antlr4/SysY.g4 b/src/antlr4/SysY.g4
index 5f6b0c8..3af810a 100644
--- a/src/antlr4/SysY.g4
+++ b/src/antlr4/SysY.g4
@@ -83,7 +83,7 @@ fragment BINARY_EXPONENT: [pP] [+-]? DEC_DIGIT+;
 /*===-------------------------------------------===*/
 
 compUnit
-    : topLevelItem* EOF
+    : topLevelItem (topLevelItem)* EOF
     ;
 
 topLevelItem
@@ -206,13 +206,12 @@ floatConst
 unaryExp
     : primaryExp
     | ID LPAREN funcRParams? RPAREN
-    | unaryOp unaryExp
+    | addUnaryOp unaryExp
     ;
 
-unaryOp
+addUnaryOp
     : ADD
     | SUB
-    | NOT
     ;
 
 funcRParams
@@ -247,8 +246,8 @@ eqExp
     ;
 
 lAndExp
-    : eqExp
-    | lAndExp AND eqExp
+    : condUnaryExp
+    | lAndExp AND condUnaryExp
     ;
 
 lOrExp
@@ -256,6 +255,11 @@ lOrExp
     | lOrExp OR lAndExp
     ;
 
+condUnaryExp
+    : eqExp
+    | NOT condUnaryExp
+    ;
+
 constExp
     : addExp
     ;