Useful for speaking and writing: CAE (essays, proposals, formal letters, reports, reviews), CPE (essays, semi-formal/neutral and formal articles, formal letters, reports, reviews) IELTS (essays)

Alleviate – to relieve; to improve partially: alleviate hunger/poverty/stress/suffering/traffic congestion

 wordinfo.info

Arbitrary-not based on reason or evidence: arbitrary rules/assumptions/decisions/restrictions/events

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Comprehensive-of large scope; covering or involving much; inclusive: comprehensive classification/definition/knowledge/measure/survey/study/system/theory/view   

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