Expected Identifiers '(' before 'Synthesize"

What does the '(' mean?

And the code im having trouble with is

#import <UIKit/UIKit.h>

@interface ZelNoteAppDelegate : NSObject <UIApplicationDelegate> {        
开发者_开发技巧   UIWindow *window;        
   UITextField *textfield;      
   UITextView *textview;        
}

@property (nonatomic, retain) IBOutlet UIWindow *window;    
(@synthesize, @dynamic UITextField *textfield;    
@synthesize, @dynamic UITextView *textview;    
@end

---

#import <UIKit/UIKit.h>

@interface ZelNoteAppDelegate : NSObject <UIApplicationDelegate> {        
   UIWindow *window;        
   UITextField *textfield;      
   UITextView *textview;        
}
@property (nonatomic, retain) IBOutlet UIWindow *window;
@property (nonatomic, retain) UITextField *textfield;    
@property (nonatomic, retain) UITextView *textview;    
@end

@interface ZelNoteAppDelegate 
@synthesize window, textField, textView;
// ...
@end

It would help you to read again The Objective-C Programming Language.