Klingon

Esperanto, Ido, Interlingua, Klingon, Lojban, Na'vi and Volapük are constructed languages.

I can't speak Klingon.

Do you speak Klingon?

I don't speak any Klingon.

Are you ready to study Klingon?

I speak Klingon to you.

Learning Klingon will serve him well in his business career.

I didn't envision him as a Klingon speaker; his forehead was too smooth.

Good news! This is the four hundred forty-fourth sentence in Klingon.

Tatoeba now contains five hundred fifty-five Klingon sentences.

SPOCK: Captain, we've reached the designated position for scanning the coded directive tape. KIRK: Good. We've both guessed right. Negotiations with the Klingon Empire are on the verge of breaking down. Starfleet Command anticipates a surprise attack. We are to proceed to Organia and take whatever steps are necessary to prevent the Klingons from using it as a base.

You might be familiar with more a priori conlangs than you think: The Klingon language from the television series "Star Trek," the Na’vi language from the movie "Avatar," and the Dothraki language from the television series "Game of Thrones" are all examples of a priori languages.