Digraphs and Trigraphs, in Plain English

A digraph is two letters that make one sound. The sh in shop, the ai in rain, the ck in duck. A trigraph is the same idea with three letters: the igh in night, the air in chair, the ear in hear. Your child is not supposed to read those letters one at a time. They are supposed to spot the group, say the single sound it stands for, and keep going. That is the whole idea. Everything below is detail, and none of it needs you to become a teacher.

What is a digraph, exactly?

Two letters, one sound. That is the definition, and it is worth holding on to because it is the bit that confuses children when nobody says it out loud.

In ship, there are four letters and three sounds: sh, i, p. In chin, four letters and three sounds: ch, i, n. In duck, four letters and three sounds: d, u, ck. A child who reads d-u-c-k as four separate sounds will not arrive at duck, because there is no such thing as a c sound followed by a k sound in that word. The two letters are a team.

Digraphs come in two flavours. Consonant digraphs such as sh, ch, th, ng, nk, ck and qu. Vowel digraphs such as ai, ee, oa, oo, ar, or, ur, ow, oi and er. Most schemes teach the consonant ones first, because they turn up in short, useful words.

A digraph is not two sounds said quickly. It is one sound that happens to need two letters to write it down.

And a trigraph?

Three letters, still one sound. There are not many, which is good news.

The common ones are igh as in light and high, air as in fair and stairs, and ear as in near and year. Some schemes also teach ure, as in sure and pure.

Children usually cope with trigraphs better than adults expect, because by the time they meet them they have already accepted the idea that a sound can be spelled with more than one letter. The jump from two letters to three is smaller than the jump from one to two. If your child stumbles on night, it is rarely the igh that has caught them out. It is more often that they were reading letter by letter out of habit and the habit has not broken yet.

Why does my child's book call it something else?

Because schools use the word their scheme uses, and the schemes do not agree.

In Read Write Inc, digraphs and trigraphs are called special friends, defined as two or three letters that make one sound. Children are taught to find the special friends in a word first, then sound out what is left. In Sounds-Write, the language is different again: children talk about sounds and spellings, and one of the core ideas is that a sound can be written with one, two, three or four letters. In Essential Letters and Sounds, Little Wandle and Bug Club Phonics you will hear the plain words digraph and trigraph, usually alongside a phase number.

None of this changes what your child is doing. It only changes the label. If you are not sure which scheme your school uses, the book in the bag usually tells you, and the tells are fairly reliable.

When does my child get taught them?

Earlier than most parents expect. Consonant digraphs usually arrive in the first year of school, often before Christmas.

If your child's school uses a phase number, the phases are worth a quick read so you know what is coming next rather than what has already gone.

Is a blend the same as a digraph?

No, and this is the single most useful distinction for a parent to hold. A digraph is two letters making one sound. A blend, or adjacent consonants, is two letters making two sounds that sit next to each other.

In stop, the s and the t are two separate sounds. You can hear both. In shop, the s and the h are one sound and you cannot hear an s in it at all. Same position in the word, completely different job.

Most schemes give adjacent consonants their own stretch of teaching, and in nearly every scheme that stretch introduces no new sounds at all. Bug Club calls it Yellow. Little Wandle and Letters and Sounds call it Phase 4. Sounds-Write spreads it across Units 8 to 10, with words such as lamp, stop and strap. Parents often read that as a term where nothing happened. It is actually the term where the sounds already learned get harder to hold in order.

What about split digraphs?

A split digraph is a vowel digraph with a consonant wedged in the middle. In cake, the a and the e are working together, with the k sitting between them. It is written a-e.

The set is small: a-e, e-e, i-e, o-e and u-e, as in cake, these, time, home and cube. They arrive later than ordinary digraphs, usually in Year 1. Bug Club puts them in Blue 2, Letters and Sounds in Phase 5, Twinkl in Level 5, Read Write Inc inside Set 3.

My child sounds out every letter separately. What do I do?

Point, do not explain. Put your finger under the digraph so the two letters are covered as a pair, and say the sound for them. Then move your finger on. You are showing them the grouping, not teaching them a rule.

If they stall on a whole word, wait five seconds before you step in. Most children get there at about four, and the ones who are rescued at two stop trying. When you do help, give the sounds rather than the word: sh-o-p hands them the win, and shop takes it away.

And if the word is one that cannot be sounded out at all, such as said or the, just tell them and move on. There is nothing to work out. Schemes call these tricky words, red words or harder to read and spell words, depending on the scheme, but they all mean the same thing.

Why does the same digraph sound different in different words?

Because English does that, and your child's scheme knows it does.

The clearest example is oo, which is one sound in book and a different sound in moon. Jolly Phonics teaches both in Group 5 and treats them as two separate sounds that share a spelling. Read Write Inc teaches both in Set 2 and names them by example word. The same happens with ow, which behaves one way in blow and another in brown.

When your child reads one and means the other, they have not made a mistake so much as picked the wrong member of a pair. The fix is short: say the other one, let them hear which makes a real word, carry on.

Does the word "digraph" itself matter?

Not much, for you. It matters enormously for them, in the sense that the skill matters. The label is just a handle.

What is worth knowing is that a book sent home is chosen so that every digraph in it has already been taught. That is what makes it decodable for that child, and it is why the book can look far too easy. Easy is the point. Fluency is built by reading easy text quickly, not hard text slowly.

Where to go next

If you want to see the idea working, look at the next book that comes home and find one digraph on the first page. That is usually enough to make the rest of the page make sense.

Lindo Phonics is not connected to Essential Letters and Sounds and is not endorsed by them. We match the published progression so a story only uses sounds your child has already been taught. The Oxford Owl parent pages are a reasonable place to hear the sounds said cleanly if you would like to check your own pronunciation: oxfordowl.co.uk.