monad造句

1、Is there a monad that doesn't have a corresponding monad transformer ?
是有一个单子，没有相应的单子转换器(除IO) ？

2、To go further, introducing something like a Parser monad is a favorite example of mine.
更进一步，将像一个解析器的单子是我最喜欢的例子。

3、As always, the IO monad is special and difficult to reason about.
一如既往，IO单子是特别困难的原因有关。