What is a Vowel?

Children in the U.S. learning the fundamentals of reading are taught to remember ‘a, e, i, o, u, and sometimes y.’ Thus, they are taught about vowels, speech sounds made when a person’s vocal tract is open. Consonants, speech sounds made when a person’s air stream is partially obstructed by mouth, teeth, lips, and other speech organs, are the other 20 letters of the alphabet.

Vowels and consonants are the building blocks of English spelling and pronunciation. The terms vowel and consonant refer to both the sounds produced and letters used to represent the sounds.

The larynx, or vocal cords, do not constrict when vowel sounds are produced. Vowels emanate in a relaxed fashion from the larynx. Along with this, a vibration can be felt when saying vowel sounds alone. Due to this vibrating, vowel sounds are described as ‘voiced’ articulations. The consonants /b/, /d/, /g/, /j/, /v/, /z/, /th/ as in that, and /w/ as in wail are voiced; all other consonants are unvoiced. Think of the ‘om’ sound people make when they meditate. Holding vowel sounds for a long time before producing the consonant sound /m/ is relaxing due to the vowel sound vibrating.

The vocal organs produce human speech sounds.

There are approximately three vowel sounds to every vowel letter in English. If r-controlled vowel sounds in words like stir or fur are included, the total number of vowel sounds is usually considered to be fifteen; otherwise, it’s usually considered to be fourteen. In terms of English vowel letters, the total number is usually given as five plus one or two: a, e, i, o, u, and sometimes y and sometimes w.

In other languages, Spanish for instance, there is a more strict 1:1 correspondence between a vowel letter and its sound. The fact that there isn’t one letter for each distinct English vowel sound makes learning the spellings challenging.

What is a Digraph?

A digraph is two letters producing one sound. A digraph can be formed by two consonants. It can also be formed by two vowels. The term digraph is comprised of the Greek di + graph, or twice + something written.

Digraphs are common in English, so much so that beginning readers will encounter them in their earliest forays into literacy. Vowel digraphs, combinations of two vowels making a single sound, occur in words such as book, eat, and bread. Consonant digraphs, combinations of two consonants making a single sound, occur in words such as king, shoe, wish.

Key points about digraphs:

• one digraph can make more than one sound, for example, ea makes a different sound in eat than it does in bread
• digraphs can occur anywhere in a word, at its beginning, middle, or end, for example: ng and sh are the final sounds in king and wish, oo and ea occur in the middle of book and bread and ea makes the beginning sound in eat
• a digraph can consist of one letter repeated, such as oo or of two unique letters in succession, such as ea

Such complexities with vowel spellings notwithstanding, digraphs need to be addressed sooner rather than later in early literacy. That way, a rich variety of children’s literature becomes accessible to beginning readers.

The ea vowel digraph in the word bread is pronounced the same as the vowel sound in the word red.

Vowel Digraph Definition

A vowel digraph combines two vowels to make a single sound. Sounds simple and straightforward, right? And yet:

• As has already been shown, the same two vowel letters paired together can make a variety of different vowel sounds, depending on the word in which they appear.
• The same vowel sound can be represented by more than one vowel digraph.
• There are vowel digraphs consisting of two different vowels, and there are vowel digraphs consisting of the same vowel repeated.
• Depending on the source, and whether or not diphthongs, vowel pairs with two distinct sounds, are included, there are up to approximately fifteen vowel digraphs.

Consider the chart below:

Key takeaways:

• ai and ay are two different vowel digraphs, but they are pronounced the same way, as shown in words such as gain and stay
• the vowel digraph ea is pronounced differently in the words beach, bread, and break

The ea vowel digraph in the word eat has the same pronunciation as the vowel sound in the word feet.

Vowel Digraphs

Diphthongs, vowel pairs with two distinct sounds, are another thread that must be woven into the vowel digraph tapestry. Diphthongs are related to digraphs. But they are distinct, with some sources considering them to be a subset of digraphs. Other sources consider diphthongs to be an altogether separate phenomenon.

Consider the word’s Greek roots: di plus phthong, or twice plus voice or sound. Diphthongs slide two separate sounds together, with both sounds still audible. Digraphs, on the other hand, are defined as letter pairs wherein one sound results. A diphthong’s two distinct sounds merge into each other. Examples include /ou/ as in house and /oi/ as in boil.

Sources differ on what to include within the diphthong classification. In one source, ay as in play or oo as in zoo are considered diphthongs, while in another, they’re considered vowel digraphs. Pronunciation variations do occur across regions in the U.S., so that could contribute to the different classifications.

A teaching source explains that, when articulating a diphthong, the shape of the mouth undergoes a change. In contrast, while articulating a vowel digraph, the mouth shape remains the same. The same source recommends a mirror be used to help learners understand this mouth-shape difference between digraphs and diphthongs. Using a mirror helps learners to see the difference between digraphs and diphthongs for themselves.

The ea vowel digraph in break is pronounced the same as the vowel sound in the word take.

Digraph Chart

Remember, a digraph is two letters combining to make a single sound. The two letters can be two identical vowels appearing consecutively or two unique vowels in succession.

Key takeaways:

• A vowel digraph can create more than one vowel sound. For example, oo is pronounced one way in room and another way in foot. Unfortunately for the beginning reader, these spellings cannot be predicted; they simply must be learned through practice and familiarity.
• In English, the doubling of the vowels a, i, and u occur only rarely. Think aardvark, Hawaii, and vacuum.
• A vowel digraph can consist of two different vowels together.
• A vowel digraph can consist of two same vowels together.

Teaching Strategies with Digraph Examples

Digraphs should be included in reading fundamentals coursework for beginning readers. The focus should be on one vowel pair at a time. For example, the vowel letters oo could be shown visually to students. At the same time, students should hear and practice the sounds this vowel pair can make, beginning with the long u sound. Additional pronunciations can be added in later.

After teaching the vowel pair isolated from any word examples, students can begin to be shown a few words as examples, such as soon, too, school. It’s recommended that students be shown that two different vowel digraphs can make the same vowel sound. For example, both oo and oe make the long u sound, as the words moon and shoe illustrate.

Students should be taught one syllable words to start, multisyllable words later, and diphthongs last. The instruction should proceed as slowly as necessary because it takes time to absorb the complexities of vowel pairs and the sounds they represent. Multisensory teaching is recommended; by including index cards and other manipulatives, such as sound boxes, students can be helped to chunk words into their individual sounds.

Key points for teaching digraphs:

• focus on one digraph at a time
• start with the digraph alone, without bringing in examples of words
• when ready to begin with word examples, start with one-syllable words
• show students that two different vowel digraphs can make the same vowel sound, for example, ay and ai both make the long a sound, as in hay and wait
• use a multi-sensory approach involving as many senses as possible

One note of caution: the phrase ‘when two vowels go walking the first one does the talking’ is problematic and should not be used as a teaching strategy. The reason for this is simply that there are so many exceptions that the rule is rendered practically useless. Examples that fit the rule are words such as lie, boat, and true, while exceptions to the rule include words such as piece, guest, or canoe.

Lesson Summary

Vowel digraphs, combinations of two vowels making a single sound, are tricky to spell. Unlike other languages, English doesn’t have a one-to-one correspondence between spelling and pronunciation. Vowels are speech sounds made when a person’s vocal tract is open. Consonants are speech sounds made when a person’s air stream is partially obstructed by mouth, teeth, lips, and other speech organs.

Points to keep in mind:

• vowel digraphs can be two identical vowels in succession, such as ee or two different vowels in succession, such as ea
• the word vowel refers both to the sound produced and to the letter representing that sound
• it’s important to learn vowel digraphs in beginning literacy, first without word examples, then with one-syllable words grouped to show that two different vowel digraphs can make the same vowel sound (eg., ai and ay both make the long a sound, as in rain and say)
• the most common vowel digraphs are ai, ay, ee, ea, oa and oe
• depending on the source, and whether or not diphthongs are included, there are up to approximately fifteen vowel digraphs

Vowel digraphs, in all their marvelous complexity, are an essential component in early literacy instruction. Much of the best of children’s literature has many vowel digraphs, so it’s important to make them accessible to beginning readers.