occurence造句
Thispaperdealswiththefrequency,seasonalcharacter,regionaldistributionofdroughtoccurenceandrecurrenceintervalofdroughtoccurencelastingforyears.Thispaperinvestigatestheoccurenceofplasticnowlayerandforma...
Thispaperdealswiththefrequency,seasonalcharacter,regionaldistributionofdroughtoccurenceandrecurrenceintervalofdroughtoccurencelastingforyears.Thispaperinvestigatestheoccurenceofplasticnowlayerandforma...