用梯子登高时，梯脚必须要做（）措施。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='25788' and id < 2166263 and id<>'2166263' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='25788' and id > 2166263 and id<>'2166263' order by id asc limit 5