YOU SAID:
she sell she shells by the sea shore
INTO JAPANESE
彼女は海岸で砲弾を売る
BACK INTO ENGLISH
she sells cannonballs on the beach
INTO JAPANESE
彼女は浜辺で砲弾を売っている
BACK INTO ENGLISH
she sells shells on the beach
INTO JAPANESE
彼女は浜辺で貝殻を売っている
BACK INTO ENGLISH
she sells shells on the beach
You've done this before, haven't you.