Shī / gōng / rén / yuán / xiān / zài / hé / dào / zhōng / xiū / jiàn / wéi / yàn / zài / jìn / xíng / qiáo / dūn / shī / gōng施工人员先在河道中修建围堰,再进行桥墩施工。The construction workers first built a cofferdam in the river channel before constructing the bridge piers.