YOU SAID:

black socks never get dirty, the longer you wear them the blacker they get

INTO JAPANESE

黒い靴下は決して汚れません、長く履くほど黒くなります

BACK INTO ENGLISH

Black socks never get dirty, the longer they wear, the more black

INTO JAPANESE

黒い靴下は汚れることがなく、長く履くほど黒くなります

BACK INTO ENGLISH

Black socks will not get dirty and will become black the longer you wear them

INTO JAPANESE

黒い靴下は汚れることがなく、長く履くと黒くなります

BACK INTO ENGLISH

Black socks don't get dirty and will turn black if worn for a long time

INTO JAPANESE

黒い靴下は汚れることがなく、長時間着用すると黒くなります

BACK INTO ENGLISH

Black socks will not get dirty and will turn black if worn for a long time

INTO JAPANESE

黒い靴下は汚れることがなく、長時間着用すると黒くなります

BACK INTO ENGLISH

Black socks will not get dirty and will turn black if worn for a long time