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心
　
마음
심

heart, nature;
core; center;
affection

心理[심리] (of) a mental state, ways of mind
心情[심정] affection; one's feelings
心臟[심장] the heart 

平
　
평평할   평

level; ordinary;
peaceful;
weigh

平和[평화] peace, tranquility, harmony
平均[평균] average, mean
平等[평등] equal, even, impartial

正
　
바를
정

true; correct,
right, straight;
just at

正確[정확] be precise, correct, exact
正式[정식] proper(regular) form
正當[정당] just, right, proper

內
　
안
내

inside, within;
wife, woman

內容[내용] the substance, details; contents
內部[내부] the interior, the inner part
以內[이내] within

外
　
바깥      외

outside; foreign;
extraordinary

外國[외국] a foreign state
內外[내외] inside and outside; husband and wife
外交[외교] diplomacy