it didn't play any morphological role. It is a trace of Latin endings containing (-us, -ūs, -um, -ō), this phoneme is related to vowel used to connect the definite article "l" to the stem of a noun or adjective, as in domn — domnul ('lord — the lord', cf. Latin dominus). Other consonants As with other languages, Romanian interjections often use sounds beyond the normal phoneme inventory or disobey the normal phonotactical rules, by containing unusual phoneme sequences, by allowing words to be made up of only consonants, or by consisting of repetitions. Such exceptional mechanisms are needed to obtain an increased level of expressivity. Often, these interjections have multiple spellings or occasionally none at all, which accounts for the difficulty of finding the right approximation using existing letters. The following is a list of examples. A bilabial click , pronounced by rounding the lips and strongly sucking air between them, is used for urging horses to start walking. Whistling is another interjection surpassing the limits of the phoneme inventory. It is usually spelled fiu-fiu. The dental click (see also click consonants) is used in an interjection similar to the English tut-tut (or tsk-tsk), expressing concern, disappointment, disapproval, etc., and generally accompanied by frowning or a comparable facial expression. Usually two to four such clicks in a row make up the interjection; only one click is rare and more than four can be used for over-emphasis. The Romanian spelling is usually tț, ttt or țțț. The same dental click is used in another interjection, the informal equivalent of "no" (nu in Romanian). Only one click is emitted, usually as an answer to a yes-no question. Although there is rarely any accompanying sound, the usual spelling is nt or nț. A series of interjections are pronounced with the mouth shut. Depending on intonation, length, and rhythm, they can have various meanings, such as: perplexity, doubt, displeasure, tastiness, toothache, approval, etc. Possible spellings include: hm, hâm/hîm, mhm, îhî, mmm, îî, hî. Phonetically similar, but semantically different, is the English interjection ahem. Another interjection, meaning "no", is pronounced (with a high-low phonetic pitch). Possible spellings include: î-î, îm-îm, and m-m. The stress pattern is opposite to the interjection for "yes" mentioned before, pronounced (with a low-high phonetic pitch). Pfu expresses contempt or dissatisfaction and starts with the voiceless bilabial fricative , sounding like (but being different from) the English whew, which expresses relief