// create a new parser and lexer MyGrammarLexer lexer = new MyGrammarLexer(new ANTLRStringStream("some input")); CommonTokenStream tokens = new CommonTokenStream(lexer); MyGrammarParser parser = new MyGrammarParser(tokens); // create a rewrite rule subtree stream from the parse tree generated by the parser RewriteRuleSubtreeStream stream = new RewriteRuleSubtreeStream(parser.parse()); // reset the stream stream.Reset();In this example, we create a new lexer and parser from the input string "some input". We then parse the input using the parser and generate a parse tree. We create a `RewriteRuleSubtreeStream` from the parse tree and reset it using the `Reset` method. Overall, the `RewriteRuleSubtreeStream` class is used to modify parse trees during the parsing process in C# using the Antlr Library.