diff --git a/todo.pl b/todo.pl
index d7f82d4..c1028ab 100644
--- a/todo.pl
+++ b/todo.pl
@@ -47,6 +47,17 @@ new(X,Y) :-
     write(X),
     write(" as a subtask for "), 
     write(X).
+
+delete(X):- idx(X,Y), delete(Y).
+delete(X):-
+    retractall(task(X,_)),
+    retractall(requires(X,_)),
+    retractall(requires(_,X)).
+delete(X,Y):- idx(X,T), delete(T,Y).
+delete(X,Y):- idx(Y,T), delete(X,T).
+delete(X,Y):- retractall(requires(X,Y)).
+
+
 depend(X,Y) :- idx(X, Task), depend(Task, Y).
 depend(X,Y) :- idx(Y, Task), depend(X, Task).
 depend(X,Y) :-