CLR Windows Form - how to determine if a string contains palindrome words?

Question

C++ / C#

The task is simple:
Given a string of characters. Determine if a string contains palindrome words. If there is, then mark each word with a % symbol at the beginning and end of the word (for example, %stomp% ).
The thing is, I can't figure out how to do this for multiple words in a line.
Here is the code, so far for only one word per line.

private: System::Void btn_pal_Click(System::Object^  sender, System::EventArgs^  e) {
       
       if (cb_1->Checked == false && cb_2->Checked == false) {
         MessageBox::Show("Выберите способ вывода.", "Ошибка", MessageBoxButtons::OK, MessageBoxIcon::Exclamation);
         return;
       }

       String^ str = tb_words->Text;
       String^ str2 = str;
       array <wchar_t>^ mass = tb_words->Text->ToCharArray();

       int n = tb_words->Text->Length;

       bool palindrom = true;
       for (int r = 0; r < mass->Length; r++) {

         for (int i = 0; i < (n / 2); i++)
         {
           if (mass[i] != mass[n - i - 1])
           {
             palindrom = false;
             break;
           }
         }
       }

       if (palindrom) {

         if ((cb_1->Checked == true) && (cb_2->Checked == false))
         {
           tb_words->Text = "%" + str + "%";
           str = str2;
         }

         if ((cb_2->Checked == true) && (cb_1->Checked == false)) {
           lb_pal->Items->Add("%" + str + "%");
           str = str2;
         }

         if ((cb_1->Checked == true) && (cb_2->Checked == true)) {
           tb_words->Text = "%" + str + "%";
           lb_pal->Items->Add("%" + str + "%");
           str = str2;
         }
         btn_pal->Enabled = false;

       }
       
}

Please tell me how to complete the task for the entire line.

Answer 1

What does WinForms have to do with it? From assignment

Дана строка символов. Определить, есть ли в строке слова-палиндромы. 
Если есть, то отметить каждое слово символом % в начале и в конце слова (например, %топот% ).

it is clear that only two super-complicated actions are required from winforms: read a line from a textbox and write the result.
And what are you doing there with checkboxes with the speaking names cb_1 and cb_2, and other elements, nobody understands.
In general, normally divide the task into subtasks and solve them.