Diéresis

Dieresis

Spanish words that contain -gue or -gui are pronounced by omitting the u sound and making a hard g.

For example:

guerra, guerrilla, albergue, Águeda...war, guerrilla, youth hostel, Águeda (female name)...

guiso, águila, siguiente, alguien...stew, eagle, next, someone...

But there are a few words in Spanish containing -gue or -gui that are pronounced differently: the sound of the u is not omitted and the g is still hard. To indicate this, the written word uses the orthographic symbol called a "diéresis". This symbol looks like two dots above the letter u. Some examples using the dieresis are:

cigüeñastork

lingüísticalinguistics

vergüenzashame

pingüinopenguin

bilingüebilingual 

 Notice how the pronunciation varies if we do not include the dieresis:

pinguino (incorrect)penguin

pingüinopenguin

U is the only Spanish letter that can have a dieresis

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