there is regional variation, with for example the u being pronounced in a few Brazilian Portuguese accents qüestão, but not in European Portuguese questão. Although the number of words with such divergent pronunciations is small, they have been seen as an obstacle to the orthographic unification of the language. Unstressed vowels are usually high, but there are exceptions, including a few pairs of homographs in European Portuguese which vary only in having either a low or a high vowel in an unstressed syllable. To distinguish these, the grave accent was at first placed on unstressed low vowels: cf. pregar "to nail", where the e is pronounced in European Portuguese, with prègar "to preach", where è is pronounced , or molhada "wet" with mòlhada "bundle". But in Brazilian Portuguese both words in each example are pronounced the same way, so the grave accent is not used: pregar "to nail/to preach", molhada "wet/bundle"; the intended meaning is inferred from context. The grave accent was eventually abolished, except in a small number of contractions. In other cases, where an unstressed low vowel was the result of the elision of the consonants c or p before c, ç, t, the consonant was kept in the spelling, to denote the quality of the preceding vowel. For example, in the word intercepção, which is stressed on its last syllable, the letter p is not pronounced, but indicates that the second e is pronounced , as opposed to the second e in intercessão, which is pronounced . Other examples of words where a silent consonant was left to lower the previous vowel are objecção and factor. In Brazilian Portuguese, the vowels in question are pronounced just like any other unstressed vowels, and, since there is no phonetic ambiguity to undo, the words are simply spelled objeção, fator, and so on. The orthography distinguished between stressed éi and stressed ei. In Brazilian Portuguese, these diphthongs are indeed different, but in most dialects of European Portuguese both are pronounced the same way, and éi appears only by convention in some oxytone plural nouns and adjectives. This led to divergent spellings such as idéia (Brazil) and ideia (Portugal). The Brazilian spelling has a, ê or ô in several words where the European orthography has á, é or ó, due to different pronunciation. For example, cf. pensamos, gênero, tônico (Brazil) with pensámos, género, tónico (Portugal). This happens when the vowels are