everybody is ( s ) to greet others when they meet each other.
问题描述：
everybody is ( s ) to greet others when they meet each other.
答
everybody is ( supposed ) to greet others when they meet each other.
注：固定用法：be supposed to do sth 应该做某事.
翻译：大家在见面的时候应该互相打招呼.
加油!不明白再问!