diff --git a/src/func/copy_func.rs b/src/func/copy_func.rs
index 1d63dd5..0a8d8af 100644
--- a/src/func/copy_func.rs
+++ b/src/func/copy_func.rs
@@ -89,59 +89,59 @@ impl<T: ApplicativeLA2> CopyApplicativeLA2 for T {
     }
 }
 
-// pub trait CopyApplicative: CopyFunctor + CopyApplicativeSeq + CopyApplicativeLA2 {
-//     fn copy_pure<A: Copy>(a: A) -> Self::CF<A>;
+pub trait CopyApplicative: CopyFunctor + CopyApplicativeSeq + CopyApplicativeLA2 {
+    fn copy_pure<'a, A: 'a + Copy>(a: A) -> Self::CF<'a, A>;
 
-//     fn copy_discard_first<A: Copy, B: Copy>(fa: Self::CF<A>, fb: Self::CF<B>) -> Self::CF<B> {
-//         Self::copy_seq(Self::copy_replace(fa, |b| b), fb)
-//     }
+    fn copy_discard_first<'a, A: 'a + Copy, B: 'a + Copy>(fa: Self::CF<'a, A>, fb: Self::CF<'a, B>) -> Self::CF<'a, B> {
+        Self::copy_seq(Self::copy_replace(fa, |b| b), fb)
+    }
 
-//     fn copy_discard_second<A: Copy, B: Copy>(fa: Self::CF<A>, fb: Self::CF<B>) -> Self::CF<A> {
-//         Self::copy_la2(|a, _| a, fa, fb)
-//     }
-// }
+    fn copy_discard_second<'a, A: 'a + Copy, B: 'a + Copy>(fa: Self::CF<'a, A>, fb: Self::CF<'a, B>) -> Self::CF<'a, A> {
+        Self::copy_la2(|a, _| a, fa, fb)
+    }
+}
 
-// impl<T: Applicative> CopyApplicative for T {
-//     fn copy_pure<A: Copy>(a: A) -> Self::CF<A> {
-//         Self::pure(a)
-//     }
+impl<T: Applicative> CopyApplicative for T {
+    fn copy_pure<'a, A: 'a + Copy>(a: A) -> Self::CF<'a, A> {
+        Self::pure(a)
+    }
 
-//     fn copy_discard_first<A: Copy, B: Copy>(fa: Self::CF<A>, fb: Self::CF<B>) -> Self::CF<B> {
-//         Self::discard_first(fa, fb)
-//     }
+    fn copy_discard_first<'a, A: 'a + Copy, B: 'a + Copy>(fa: Self::CF<'a, A>, fb: Self::CF<'a, B>) -> Self::CF<'a, B> {
+        Self::discard_first(fa, fb)
+    }
 
-//     fn copy_discard_second<A: Copy, B: Copy>(fa: Self::CF<A>, fb: Self::CF<B>) -> Self::CF<A> {
-//         Self::discard_second(fa, fb)
-//     }
-// }
+    fn copy_discard_second<'a, A: 'a + Copy, B: 'a + Copy>(fa: Self::CF<'a, A>, fb: Self::CF<'a, B>) -> Self::CF<'a, A> {
+        Self::discard_second(fa, fb)
+    }
+}
 
-// pub trait CopyMonad: CopyApplicative {
-//     fn copy_bind<A: Copy, B: Copy, F: Copy + Fn(A) -> Self::CF<B>>(
-//         fa: Self::CF<A>,
-//         f: F,
-//     ) -> Self::CF<B>;
+pub trait CopyMonad: CopyApplicative {
+    fn copy_bind<'a, A: 'a + Copy, B: 'a + Copy, F: 'a + Copy + Fn(A) -> Self::CF<'a, B>>(
+        fa: Self::CF<'a, A>,
+        f: F,
+    ) -> Self::CF<'a, B>;
 
-//     fn copy_join<A: Copy>(ffa: Self::CF<Self::CF<A>>) -> Self::CF<A>
-//     where
-//         Self::CF<A>: Copy,
-//     {
-//         // ugly
-//         Self::copy_bind(ffa, |fa| fa)
-//     }
-// }
+    fn copy_join<'a, A: 'a + Copy>(ffa: Self::CF<'a, Self::CF<'a, A>>) -> Self::CF<'a, A>
+    where
+        Self::CF<'a, A>: 'a + Copy,
+    {
+        // ugly
+        Self::copy_bind(ffa, |fa| fa)
+    }
+}
 
-// impl<T: Monad> CopyMonad for T {
-//     fn copy_bind<A: Copy, B: Copy, F: Copy + Fn(A) -> Self::CF<B>>(
-//         fa: Self::CF<A>,
-//         f: F,
-//     ) -> Self::CF<B> {
-//         T::bind(fa, f)
-//     }
+impl<T: Monad> CopyMonad for T {
+    fn copy_bind<'a, A: 'a + Copy, B: 'a + Copy, F: 'a + Copy + Fn(A) -> Self::CF<'a, B>>(
+        fa: Self::CF<'a, A>,
+        f: F,
+    ) -> Self::CF<'a, B> {
+        T::bind(fa, f)
+    }
 
-//     fn copy_join<A: Copy>(ffa: Self::CF<Self::CF<A>>) -> Self::CF<A>
-//     where
-//         Self::CF<A>: Copy,
-//     {
-//         T::join(ffa)
-//     }
-// }
+    fn copy_join<'a, A: 'a + Copy>(ffa: Self::CF<'a, Self::CF<'a, A>>) -> Self::CF<'a, A>
+    where
+        Self::CF<'a, A>: 'a + Copy,
+    {
+        T::join(ffa)
+    }
+}