人字梯应具有坚固的较链和限制开度的（）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='25758' and id < 2164472 and id<>'2164472' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='25758' and id > 2164472 and id<>'2164472' order by id asc limit 5