wéi xiū rén yuán / xiān / qiē duàn / diàn yuán / zài / jiǎn chá / diàn yì / de / chù diǎn / shì fǒu / yǐ jīng / yǎng huà

维修人员先切断电源，再检查电驿的触点是否已经氧化。

The maintenance staff first cut off the power and then checked whether the relay contacts had oxidized.