to be ready to help one's comrades.这句话怎么译,one's代表什么意思?

one's 以为"某人的",用物主代词替换,以下是一些例子.
to be ready to help my comrades,
to be ready to help his comrades,
to be ready to help Xiao Ming's comrades,
to be ready to help my grandma's comrades.