
You don't have to,
but it's HIGHLY recommended.
The Big Bang Theory Season 3, Episode 2

Well, an audit can be
HIGHLY motivating.
Breaking Bad Season 4, Episode 3

...HIGHLY active, HIGHLY profitable
marketplace.
Breaking Bad Season 5, Episode 8

You spoke so HIGHLY of Jon Snow,
Game of Thrones Season 7, Episode 3

SHELDON:
Highly.
The Big Bang Theory Season 4, Episode 4