Moderator note: split from another thread Generally, when words are borrowed as-they-are and are felt unanalyzable (meaning, not originating from the traditional root and pattern mold), when a root has to be extracted from it, speakers tend to prefer transparency: they choose a root and a binyan that preserve the consonant clusters and the alternation of consonants and vowels. For that reason, almost if not all borrowed verbs are in the PI'EL, HIF'IL and HITPA'EL, since consonant clusters are preserved in all tenses and forms. QAL and NIF'AL rearrange consonant clusters throughout their paradigm and are not felt as "transparent" binyans : liQToL / QaTaL, niQTaL / hiQQaTeL. For instance, "to fax" : - we can't choose to extract the root F-K-S in the QAL since hu fakas / hu fokes / lifkos transforms the original word beyond recognition. - we can't choose to extract the root F-K-S in the PI'EL since hu fikkes / hu mefakkes / lefakkes, even though consonant/vowel alternation is stable throughout, since we lose the orignal word's alternation F-vowel-KS, it can't be preferred. - we actually choose to extract the root F-KS-S in the PI'EL : hu fikses / hu mefakses / lefakses, which preserves the F-vowel-KS pattern found in the original word. Other examples are: - flirt : flirtet, with root FL-R-T-T, binayn PI'EL - spritz : hishpritz, with root Sh-PR-TZ, binayn HIF'IL There's a fair amount of literature on the subject, cf. for instance "Measuring Productivity in Word Formation: The Case of Israeli Hebrew" by Bolozky.