下面这句英文句子,用了什么语法
问题描述：
下面这句英文句子,用了什么语法
At present,the Chinese people stay focused on the primary task of development,working together with full confidence to build a moderately prosperous society in all respects and striving to achieve modernization.
答
动词ing起解释说明作做用,working 和striving是并列的,解释说明rimary task of development.