In addition to synalepha across word boundaries, sequences of vowels in hiatus become diphthongs in fast speech; when this happens, one vowel becomes non-syllabic (unless they are the same vowel, in which case they fuse together) as in "poeta" ('poet') and "maestro" ('teacher'). Similarly, the relatively rare diphthong may be reduced to in certain unstressed contexts, as in "Eufemia", . In the case of verbs like "aliviar" ('relieve'), diphthongs result from the suffixation of normal verbal morphology onto a stem-final (that is, "aliviar" would be || + ||). This contrasts with verbs like "ampliar" ('to extend') which, by their verbal morphology, seem to have stems ending in . Spanish also possesses triphthongs like and, in dialects that use a second person plural conjugation, , , and (e.g. "buey", 'ox'; "cambiáis", 'you change'; "cambiéis", '(that) you may change'; and "averiguáis", 'you ascertain').