齿轮的点蚀，是因为（ ）造成的。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='24894' and id < 2124496 and id<>'2124496' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='24894' and id > 2124496 and id<>'2124496' order by id asc limit 5