请翻译：目前已成功举办四届

例句给你：
Six Kunming Export Fairs, approved by the State MOFTEC, have been successfully held under the joint efforts of six provinces, regions and cities as well as seven parties of Southwest China.
其中，经国家对外经济贸易合作部批准，由中国西南六省区市七方联合主办的昆明出口商品交易会，至今已成功举办了六届。

(主语)目前已成功举办四届(宾语补足语)

We have been successfully held four...

该句要注意语态!演说者在表达过去已经完成的事情,现在已经完成了,所以用的是现在完成时语态!

Up to now we have sucessfully hosted four.....(conferences, meetings)

"xxx has been successfully held 4 times by now"

xxx换成活动名称即可

Presently (we have) successfully held the functions for four times (four years, four terms ...)