NSMutableString *ms = [[NSMutableString alloc] initWithString:@"我是中國人"];
        if (CFStringTransform((__bridge CFMutableStringRef)ms, 0, kCFStringTransformMandarinLatin, NO)) {
            NSLog(@"Pingying: %@", ms); // wǒ shì zhōng guó rén
        }
        if (CFStringTransform((__bridge CFMutableStringRef)ms, 0, kCFStringTransformStripDiacritics, NO)) {
            NSLog(@"Pingying: %@", ms); // wo shi zhong guo ren
        }