英语语法分析

Two weeks ago they began appearing in stingingly negative TV ads aired in crucial states where currently undecided voters will probably determine the outcome of the election.

两周前，他们开始出现在尖刻的负面电视广告中，这批广告在一些将对大选结果起关键性影响的州播出了，而这些州目前尚未作出决定的选民将很可能决定大选的结果。