犯人，反对，反对派，反对党 & A Problem from Hell...

犯 

this "fan4" 犯 means criminal, to violate. Much more than in English Chinese more often nominalizes verbs and verbalizes nouns. German does that all the time. 

Fan is a combined concept character. ACTED LIKE A DOG, 犭NOW DOWN ON HIS KNEES  卩   pronunciation clue. 犬quAN rhymes with fAN quan+jie=fan4.

犯人

fanren criminal

反

This fan3 means to oppose. It's the image of a hand 又 hitting up AGAINST a cliff 厂 as the idea of oppose, against. 厂 is also a phonetic clue (han3/chang3 sounds like fan3)

反对 

fandui Oppose = Against+Right

反对派

fan dui pai opposition party / opposition faction

pai in Chinese may be a faction (De. Fraktion) or a party or even a clique.

反对党

fan dui dang oppose a political party

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