diff --git a/TracerOnJavassist/src/tracer/OutputStatementsGenerator.java b/TracerOnJavassist/src/tracer/OutputStatementsGenerator.java
index f4e2011..c9a92de 100644
--- a/TracerOnJavassist/src/tracer/OutputStatementsGenerator.java
+++ b/TracerOnJavassist/src/tracer/OutputStatementsGenerator.java
@@ -72,15 +72,15 @@
 	}
 	
 	public String generateReplaceStatementsForCall(CtClass cls, CtBehavior m) throws NotFoundException {
-		return generateInsertBeforeStatements(cls, m, true) + " $_ = $proceed($$); " + generateInsertAfterStatements(cls, m, true);
+		return "{" + generateInsertBeforeStatements(cls, m, true) + " $_ = $proceed($$); " + generateInsertAfterStatements(cls, m, true) + "}";
 	}
 	
 	public String generateInsertBeforeStatementsForMethodBody(CtClass cls, CtBehavior m) throws NotFoundException {
-		return generateInsertBeforeStatements(cls, m, false);
+		return "{" + generateInsertBeforeStatements(cls, m, false) + "}";
 	}
 	
 	public String generateInsertAfterStatementsForMethodBody(CtClass cls, CtBehavior m) throws NotFoundException {
-		return generateInsertAfterStatements(cls, m, false);
+		return "{" + generateInsertAfterStatements(cls, m, false) + "}";
 	}
 		
 	/**