flood prevention in flood season
Workers in the oil field
Drought and flood in flood season
flood in the south and drought in the north
Flood in the summer 1998
Geological hazards in the flood season
in the flood recession period
trust in flood prevention projects
Lightning prevention in the rural areas
policy of prevention in the first place and integrating prevention with control
Acquisition and manipulation of data in the field
Ansai oil field in Changqing
application of maize stalk in the field
Baibao oil field in Changqing
Chaoyanggou oil field in Daqing
Commission Initiative in the Field ofthe Environ
control efficacy in the field
co-operation in the field of scientific and technological research
correct value of temperature measure in the field