감소reduction 감소율reduction ratio 감점point deduction 급감rapid decrease; sharp fall; nosedive 증감fluctuation 탕감cut; reduction; curtailment; slashing 가감addition and subtraction; adjustment 가감승제addition, subtraction, multiplication and division 감량weight reduction; weight loss 감면reduction; exemption

속도speed 고속high speed 과속speeding 속도위반speeding violation 초고속superhigh speed; ultrafast speed 초속speed per second 쾌속high speed 쾌속선fast boat; high-speed boat 쾌속정fast boat; high-speed boat 풍속wind velocity