扬声器系统安装中涉及承重结构改动或增加负荷时，必须经（）确认后方可实施。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='28964' and id < 2357926 and id<>'2357926' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='28964' and id > 2357926 and id<>'2357926' order by id asc limit 5