At the Chinese dinner table，the medial position facing the door is for VIP和 Eating won't start until the person sitting right in the middle has a taste of the food。之中的facing和sitting，为什么要用doing
非谓语，主动用doing 被动用done 给你分析一下句子：the medial position is for VIP和Eating won't start until the person has a taste of the food都已经是完整的句子了，这时候还能加的就是状语，或定语了 你可以用定语从句，或者非谓语 facing the door=which faces the door sitting right in the middle=who sits right in the middle