根据下面短文内容，在短文的空格处填上一个恰当的词，使短文完整、通顺．

When you talk with someone，you'll need to end your conversation at some point．And there are many reasons why you need to do that．Either you or the other person may need to continue an activity such （78） 　　working or shopping．Or you may have run out of things to say．You just want to keep the conversation short．

But（79） 　　do you end a conversation in a polite way？It may depend on where and how the conversation started．It may also depend on your relationship with the（80） 　　person．If you already know that person，you can just say，"I need to run now．"Or you can say，"I'll catch you later．"You may also give a reason for ending the conversation．"I really need to go﹣my piano class starts in ten （81） 　　．"

Perhaps you just meet someone in a social situation，and you have a nice talk．But then you have to go．You can say，"It was nice meeting you．Maybe we can talk happily（82） 　　sometime in the future．"

Another way to end a conversation is to make it easy for the other person to （83） 　　．If you see the other person is already not patient，you can say，"Well，I'm sure you have a lot to do today．"

You could use these （84） 　　to end a conversation，and you should notice that others may also use them．（85） 　　they do so，you should know that it's time for you to stop and get on with your day．