later on和since then有什么区别，各自用法怎样？

later on和since then有什么区别，各自用法怎样？

later on adv. 后来；稍后；过些时候
过后，以后，下回如：1、Let us recur to the subject later on.
让我们稍后再重回到我们的主题。
2、I may have to ask for your advice later on.
以后少不得要去向您讨教。

since then从那时以来，现在完成时标志。如：1、Since then he has been drawing a pension. 从那时起他一直领退休金。 2、He has never been able to rekindle her love since then. 从那时起他再也不能激发起她的爱情。
3、Since then, we've lived far apart and never

seen each other again.

从那以后， 我们山南海北再也没有见过面。

前者 是后来 用于将来（尤其是那种讲故事的文体） 后者是 从那时起 一般和完成时连用.

later on adv. 后来；稍后；过些时候 过后，以后，下回如：1、let us recur to the subject later on. 让我们稍后再重回到我们的主题。 2、i may have to ask for your advice later on. 以后少不得要去向您讨教。 since then从那时以来，现在完成时标志。如：1、since then he has been drawing a pension. 从那时起他一直领退休金。 2、he has never been able to rekindle her love since then. 从那时起他再也不能激发起她的爱情。 3、since then, we've lived far apart and never seen each other again. 从那以后， 我们山南海北再也没有见过面。