2 sentences

1. 他们共同努力促进了经济发展。

   tā​men gòng​tóng nǔ​lì cù​jìn le jīng​jì fā​zhǎn.

   Their joint efforts promoted economic development.

   Source: Dong Chinese Dictionary

2. 双方的共同努力促成了这次合作。

   shuāng​fāng de gòng​tóng nǔ​lì cù​chéng le zhè cì hé​zuò.

   The joint efforts of both parties brought about this cooperation.

   Source: Dong Chinese Dictionary