YOU SAID:
Because I lost my favorite toy.
INTO JAPANESE
大好きなおもちゃを失くしてしまったからです。
BACK INTO ENGLISH
Because he lost his favorite toy.
INTO JAPANESE
お気に入りのおもちゃをなくしてしまったからです。
BACK INTO ENGLISH
Because he lost his favorite toy.
You've done this before, haven't you.