当电路中电流的参考方向与实际方向相反时，该电流不能确定是正值或负值。（   ）

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69348' and id < 4489443 and id<>'4489443' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='69348' and id > 4489443 and id<>'4489443' order by id asc limit 5