YOU SAID:

Antoine is a boy who isn't very nice, but very intelligent.

INTO JAPANESE

アントワーヌは非常に良いが、非常に理性的ではない少年です。

BACK INTO ENGLISH

It is Antoine is very good, but not very intelligent boy.

INTO JAPANESE

アントワーヌは、非常に良いが、非常に理性的ではない少年です。

BACK INTO ENGLISH

It is Antoine is very good, but not very intelligent boy.