四孔的三相电源插座上没有哪根线？（ ）

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SQL Error: select id,body,options from ***_enewstiku where sourceid='30395' and id < 2457171 and id<>'2457171' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30395' and id > 2457171 and id<>'2457171' order by id asc limit 5