we have been invited to attend the party后面用holding还是 being held为什么?感激不尽〜

we have been invited to attend the party
后面用holding还是 being held
为什么?
感激不尽〜

选 being held.
后置定语,修饰 party；意思是 “正在举办中的”
being held 是 被动语态进行式