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有
있을유

exist, be;
have, possess

有名[유명]be famous, well-known
有力[유력]be influential; convincing, powerful
有望[유망]full of promise, hopeful
有無[유무]whether there is or not

無
없을무

nothing, nil;
not having

無視[무시]ignore, disregard
無線[무선]radio, wireless
無事[무사]safely, without incident

比
비할비

compare

比較[비교]compare
比例[비례]comparison; proportion, ratio
比率[비율]ratio, percentage

前
앞전

front; before

前後[전후]before and after; about, approximately
前進[전진]advance
前例[전례]precedent, previous example

後
뒤후

after, behind,
later

後方[후방]the rear, rear area
後悔[후회]regret, be sorry for
後退[후퇴](military) retreat