The first and third work, but not the second. Why? Michael ============== f :: String -> IO () f s = do putStrLn s {- g :: [String] -> IO () g l = do s <- l          putStrLn s -} {- h :: [Int] -> [Int] h l = do i <- l          return (i+1) -} ============== serialize2.hs:29:9:     Couldn't match expected type `[String]'            against inferred type `IO String'     In a stmt of a 'do' expression: s <- l     In the expression:         do { s <- l;              putStrLn s }     In the definition of `g':         g l = do { s <- l;                    putStrLn s }