Each vowel has only one pronunciation and it will be pronounced that way in every Spanish word. Except for the gu and qu combination, there are no silent vowels in Spanish. Some vowels will slur together to create a single sound. These vowel combinations are called diphthongs.
Correct pronunciation of vowels is especially important when you pronounce a word that looks like an English word. Remember, a lot of Spanish words look similar to English words, and some are even spelled exactly the same. However, these cognates are never pronounced exactly like their English equivalents. Also, a Spanish word that is pronounced like an English word will probably be spelled differently in Spanish. When you recognize a cognate, take your time and pronounce the vowels carefully.
Models for vowel pronunciation
A few common Spanish words can serve as models for your pronunciation. Everyone knows how to pronounce the word taco. The letters a and o are always pronounced as they are in taco. A heavy Spanish accent will result in English words like “hat” or “can” sounding more like the English words “hot” or “con.” That is because the native Spanish speaker is saying the letter a the only way it can be said in Spanish. As for the letter o in taco, it is shorter in Spanish and doesn't end in a wa sound.
Another word you have probably learned courtesy of the popularity of Mexican food is burrito. The Spanish vowels u and i are always pronounced as they are in this word.
The final Spanish vowel left to master is the e. It is always pronounced like the e in café. (To see how well you're learning, make sure you are pronouncing the a in café correctly. It should sound like the a in taco.) Also, an e at the end of a word is not silent as it is in the English word “rake.” Remember that there are no silent vowels in Spanish (except for the qu and gu issue), so you must say ay at the end of cognates that end in e.
Vowel combinations
The strong vowels are a, o, and e. When two strong vowels appear next to each other in a word, the result is two separate syllables with both vowels strongly pronounced. If one of the strong vowels is used beside a weak vowel ( i or u), the resulting single syllable, called a diphthong, is a slur of the two vowels with the stronger vowel the only one that is clearly heard.
If the weak vowels i and u are combined, the result is one syllable, with the first weak vowel slurred over and the second one fully pronounced. (Remember that, in the battle of the weak vowels, the last one gets stressed.) When a weak vowel precedes a strong vowel, the weak vowel acts as a consonant. The u creates the sound of an English w; the i sounds like the consonant y.
Consonants as vowels
The letter y acts as a vowel only when it stands alone or when it is at the end of the word. In such instances, it is pronounced like the i in burrito. As a consonant, the Spanish y sounds just like it does in the English word “you.”
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