For additional occurrences of both the O and the E sounds see the sub-division on 'Irregular Verb Forms', pages 44-46.
You know, of course, that Spanish has no such thing as a nasal vowel. Nor does English, for that matter. So the process of pronouncing a vowel 'through your nose', as the saying goes, may be new to you. Rest assured, though, that it is not a particularly difficult thing for most people to learn to do.
Portuguese has five nasal vowels. They are:
ẽ ĩ õ ũ and ã
In our modified spelling we will use the tilde (~). In standard spelling, nasal vowels are frequently signalled by the presence of an m or n after the vowel in the same syllable, as in vendo, sim, bom, ums, and banda. In addition, the tilde designates many õ and ã sounds (the latter being written ãe).
It is important to remember that these nasal vowels are not mere variations of their non-nasal, or oral, counterparts. They are completely different vowels, every bit as distinct from the non-nasals as a is from o and as i is from u.
The nasal vowels show up frequently in easily recognizable Spanish/Portuguese cognate words. In the Spanish version of these words, you first pronounce the vowel, then you pronounce an m or n sound. In Portuguese, however, you simply nasalize the vowel. That's all. You do not pronounce an m or an n. If you do, nobody will have any trouble understanding you, but your Portuguese will be more Spanish than you should want it to be. Be alert then to the changes you will have to make in such cognate items as the following:
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