What in the world are Spanish Diphthongs?

Spanish vowels

Understanding what a diphthong is, how to pronounce them and the use of accent marks on Spanish diphthongs.

The textbook definition of a diphthong is "the union of two vowels in one syllable".

Meaning that when two vowels are pronounced together in the same syllable, it is called a diphthong.

• auto (ahw-toh) automobile/car
• piano (pyah-noh) piano
• baile (bi-leh) dance

strong vowels = a, e and o

weak vowels = i and u

If a strong vowel is placed with a weak vowel, which applies in most cases, then the i is pronounced somewhat like the y in yes and the u is pronounced like the w in when.

• historia (is-tor-eeya) history
• seis (seys) six
• suave (soowa-vey) smooth

One of the rules is that when two strong vowels, a,e, and o are placed next to one another they need to be pronounced as separate syllables. Now the diphthong is broken.

• poeta (poh-ehta) poet
• traer (trah-ehr) to get/fetch
• oasis (oh-ah-sis) oasis

Sometimes these broken diphthongs also have Spanish accent marks placed over them to indicate where the stress is placed during pronunciation.

Notice they are already broken because 2 strong vowels appear next to one another, and the accent mark simply denotes where the stress is placed.

• aéreo (ah-ehr -ee-oh) air/aerial
• océano (ohsay -ahnoh) ocean
  

Another version of a broken diphthong is when the accent mark is placed above the i or the u indicate stress. The two vowels are then pronounced separately in different syllables.

• día (dee-yah) day
• biología (byo-loghee-yah) biology
• increíble (in-crey-ee-bleh) incredible

A common example is the name María. Without the accent mark, the name would be pronounced much like mahr-yah. In effect, the accent mark turns the i into a strong vowel making the pronunciation mahr-ree-ya

The Spanish letters g (which you can see in action on my pronounce Spanish page) and the letter q, (on my letters of the Spanish alphabet page), are some more examples of Spanish diphthongs.