There are specific rules in Spanish regarding pronunciation of words regarding to how stress is used, it would be a lot clearer if you could listen to the following words but we will endeavor to highlight the basic rules as applied to the Spanish language from this point.

1# Most words that ed in a vowel, "n" or "s" take the stress on the penultimate syllable: e.g: "hombre" (man) the stress would be on the "o" so it would be pronounced [Om-bray].

2# Most words that end in a consonant other than "n" or "s" take the stress on the last syllable: e.g: "ciudad" (city) is stressed on the "a" so it would be pronounced [thee-oo-dAd].

3# When there is an exception to either of these two rules a written accent is used on the stressed syllable: e.g: "estación" (station) [ess-tah-the-'On].

4# The written accent is also used to distinguish between words that have the same spelling: e.g: el (the) él (he); mas (but) más (more).

5# In Spanish "a", "e" and "o" are strong vowels, "i" and "u" weak when two strong vowels come together they are both pronounced: e.g: paella [pah-ay-lya].

When two weak vowels come together the stress is on the last vowel and when a strong and a weak vowel come together the strong one is always stressed unless the weak one has an accent.

Punctuations and Accents:

Question marks and exclamation marks are placed at either end of a sentence with the one at the start of the sentence inverted.

¿Dónde está el coche? [Where is the car?]

The tilde is the wavy little line that is situated above the “ñ” in Spanish and is pronounced “ni” as in onion.

The “diaeresis”, are two little dots above a letter that mean that the letter must be pronounced; in Spanish they are used above the letter “ü” when “u” is preceded by the letter “g”.

Finally, the written accent; as explained above, it is used to signify a stressed vowel that operates outside the normal rules of vowel stress, and is also used to distinguish between similarly spelt words. The other use for the written accent is for words that denote a question, such as dónde (where) and cuándo (when), but when these same words are used in a non question format the accent should be dropped.

Stress is much better understood when you can hear examples rather than read them so it is advisable to use an audio commentary whenever possible.
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