I didn’t realise that as well as speaking differently, people with different languages um… pause differently too. According to the New York Times,
The French say something that sounds like euh, and Hebrew speakers say ehhh. Serbs and Croats say ovay, and the Turks say mmmmm. The Japanese say eto (eh-to) and ano (ah-no), the Spanish este, and Mandarin speakers neige (NEH-guh) and jiege (JEH-guh). In Dutch and German you can say uh, um, mmm. In Swedish it’s eh, ah, aah, m, mm, hmm, ooh, a and oh; in Norwegian, e, eh, m and hm.
For what it’s worth my totally bilingual wife sometimes uses the ‘French um’ when speaking English and vice versa…