diff --git a/src/main/c/hangman.c b/src/main/c/hangman.c
index 1be3268..be37548 100644
--- a/src/main/c/hangman.c
+++ b/src/main/c/hangman.c
@@ -19,6 +19,7 @@ void add_guessed_letter(char* guessed_letters, char guessed_letter);
 char eingabe_buchstabe();
 void lade_secret_word(char* secret_word, int level, char* path);
 void show_letters(char secret_word[100], char guessed_letters[100]);
+int letter_in_secret_word(char guessed_letter, char secret_word[100]);
 
 void protokoll(){
 	clear_screen();
@@ -306,4 +307,13 @@ void show_letters(char secret_word[100], char guessed_letters[100]){
 		}
 	}
 	printf("\n");
+}
+
+int letter_in_secret_word(char guessed_letter, char secret_word[100]){
+	for(int i = 0; i < strlen(secret_word); i++){
+		if(guessed_letter == secret_word[i]){
+			return 0;
+		}
+	}
+	return 1;
 }
\ No newline at end of file