1.常用的几句,i'm sorry (然后拥抱一下);he was a good man/friend;we'll miss him;don't be sad , he/she'll be watching you in the heaven.
2.如果一定要说的话可以说pls , restrain your grief
3.可以说glad to talk to you guys, but i gotta go now, or i'll be late for (比如date, work, meeting ,etc...) 也可以说sorry i have to leave now, i have something/some bussiness/sth personal to deal with, hope i can see u again later.
老外都很通情达理,就说你有事就好了,不用绞尽脑汁想借口