we make momment on each other's work.短语也可以用所有格?

On April Fool's Day, we make fun of each other _____(happy) each other所有格是什么? 我搞不懂什么时候用所有格 例子：They know each other's favorite 为啥要用所有格? we get on well with each other 为什么用with we got on well with each other. we always have each other's back we will meet each other at ten o'clock on Thersday's morning 搞不懂到底什么时候用所有格? 例子：They know each other＇s favorite.他们相互了解对方的优 We always work together and help each other. We ought tohelp each other in our work,___? Can we make friend with each other?中文翻译? We make each other strong.中文是何意思