YOU SAID:
I don't even know what to put in.
INTO JAPANESE
私は何を入れるべきかさえ知らない。
BACK INTO ENGLISH
I do not even know what to put in.
INTO JAPANESE
私は何を入れるべきかさえ知りません。
BACK INTO ENGLISH
I do not even know what to put in.
You've done this before, haven't you.