YOU SAID:
She sold seashells by the seashore
INTO JAPANESE
彼女は海岸で貝殻を売った
BACK INTO ENGLISH
She sold seashells on the beach
INTO JAPANESE
彼女はビーチで貝殻を売った
BACK INTO ENGLISH
She sold the shells on the beach
INTO JAPANESE
彼女は浜辺で貝殻を売った
BACK INTO ENGLISH
She sold shells on the beach
INTO JAPANESE
彼女は浜辺で貝殻を売った
BACK INTO ENGLISH
She sold shells on the beach
That didn't even make that much sense in English.