Group 1 food crops 　　1.abandon
2.adversely
3.aggregate
4.cultivation
5.fertilize
6.intensify
7.irrigation
8.obtain
9.photosynthesis
10.precipitation
Group 2 disaster
1.anticipate
2.catastrophic
3.collide
4.eruption
5.famine
6.flood
7.impact
8.persevere
9.plunge
10.unleash
Group 3 evolution and migration
1.adapt
2.diverse
3.evolve
4.feature
5.generation
6.inherent
7.migration
8.physical
9.process
10.survive
Group 4 petroleum alternative
1.constraint
2.contamination
3.deplete
4.dispose of
5.elementally
6.emission
7.extinction
8.reservoir
9.shrink
10.stable
Group 5 time efficiency
1.adjust
2.arbitrary
3.denominator
4.exponentially
5.infinitesimal
6.maximize
7.parallel
8.proportion
9.rate
10.sequence
Group 6 ancient life
1.accuracy
2.adjacent
3.compress
4.feasibly
5.gut
6.integrally
7.overlap
8.retain
9.seep
10.structure
Group 7 computers
1.circulate
2.corrode
3.derive
4.detection
5.expeditiously
6.implement
7.innovative
8.installation
9.maintenance
10.simulation
Group 8 energy
1.combustion
2.component
3.convey
4.discretely
5.nucleus
6.permeate
7.rotate
8.solar
9.source
10.trigger
Group 9 memory
1.acquisition
2.anomaly
3.consciously
4.degrade
5.gap
6.indisputable
7.intervene
8.intuitively
9.recede
10.retrieve