gōng / zuò / rén / yuán / zhèng / zài / jiǎn / chá / shòu / diàn / gōng / hé / jiē / chù / wǎng / shì / fǒu / zhèng / cháng

工作人员正在检查受电弓和接触网是否正常。

The staff are checking whether the pantograph and overhead contact system are working properly.