YOU SAID:

I love JFK when he was younger.

INTO JAPANESE

私は彼が若い頃のJFKが大好きです。

BACK INTO ENGLISH

I love JFK when he was young.

INTO JAPANESE

彼が若い頃、私はJFKが大好きです。

BACK INTO ENGLISH

When he was young, I loved JFK.

INTO JAPANESE

彼が若い頃、私はJFKが大好きでした。

BACK INTO ENGLISH

When he was young, I loved JFK.