When To Use C Or K - Spelfabet

When to use c or k

53 Replies

An eight-year-old asked me the other day, “When do I use the letter C and when do I use K?”. She’s a pretty good reader but her spelling is not so great, which is why she was referred to me.

I got her to answer her own question by doing the following:

C or K at word beginnings (before vowels)

I wrote out some words like the following ones in two columns (I am in the habit of underlining letter groups that are working together to represent a single sound, so I will do this here too):

C	K
car cash cat clap clock club coin corn cot crab cross crow cup cut cue	keep keg Ken kerb key kid kind king kiss kit Kylie Kym skill skin sky

Then I gave her a highlighter pen and asked her to highlight all the letters “C” and “K”, plus the next letter:

C	K
car cash cat clap clock club coin corn cot crab cross crow cup cut cue	keep keg Ken kerb key kid kind king kiss kit Kylie Kym skill skin sky

Then I asked her to go down the list and write the letters following the letter “C” at the bottom of that column. She wrote: “A, L, O, R, U”.

Then I asked her to write the ones that follow a letter “K” at the bottom of that column and she wrote “E, I, Y”.

Then she summarised this as something like “When we’re writing the sound “k”, if the next letter is E, I or Y, we usually use a letter K. Otherwise we usually use C”.

Then I asked her to consider what would happen if we put “C” instead of “K” in the words in the right column, e.g. “ceep” not “keep”, “cing” not “king”, and she read these with a “s” as in “city”, “cell” and “cyanide”, not the sound “k”.

We summarised this as, “When the letter C has E, I or Y next, the sound is ‘s'” (the only spelling rule that works in English!).

As always in English, which steals words from all round the world, there are a few words which don’t stick to the “K is followed by E, I or Y” pattern, like “Kate”, “skate”, “koala”, “kangaroo”, “Korea” and “Kung Fu”. People who make alphabet posters and other alphabet-teaching materials have an annoying tendency to include lots of these words, and obscure the KE, KI, KY pattern. They also like to include the “n” sound spelt “KN” in words like “knight” and “knot”, adding further to the confusion.

C or K at word endings (after vowels)

Here I wrote out four lists of words like these:

CK	K	K	C
back buck deck dock duck hack mock muck neck Nick pack peck pick tack tick tuck yuck	ask book dark fork hawk milk oak park pink shriek soak speak spook stork sulk task week	bake* bike broke cake duke fake hike joke lake like make nuke sh ake smoke spike take woke	classic clinic comic critic epic garlic havoc logic mollusc music panic picnic relic topic traffic tragic tropic

* When I’m handwriting, I draw a little loop under words with “split” vowel spellings (or “bossy e”) to show that the two vowel letters are acting as a unit to represent a single sound. But I can’t do that when typing, so you’ll have to imagine little loops joining the underlined vowel letters in column 3.

I asked the student to highlight all the CK”, “K” and “C” spellings. Then we eyeballed the lists and deduced:

• That “ck” is an ending spelling in short words or syllables that end with “ack”, “eck”, “ick”, “ock” and “uck”. It is used after one-letter vowel spellings, with very few exceptions (I can only think of ”hoick’, ‘arcked’, ‘zincked’ and ‘talcked’).  She highlighted the preceding single vowel letters, so this pattern really stood out.
• Some longer words like “panic” and “traffic” just end in “C” not “CK”, and I added that there are a few little, not-very-common words, like “arc”, “disc” (the circular shape, not the computer thing, which is spelt “disk”) and “talc” that also fit in column 4, and added them.
• We tend to use the letter “K” at word and syllable endings the rest of the time, i.e. after consonants (as in “ask” and “pink”) and other vowel spellings, including “bossy e” vowels like “bake” and “like”.

I wrote the words “brake”, “fake”, “like”, “trike” and “puke” out in pencil, then asked her to change the “K” to a “C” and see what happened. This changed them into “brace”, “face”, “lice”, “trice” and “puce”. The student was able to tell me this was because the letter “C” sounds like “s” when a letter “E” is next. Good girl.

When we’d finished, she picked up the sheets of paper on which we had done this working-out, and asked, “Can I keep these?”. Nice one. Of course. I hope she’s going to play teacher to a friend or younger sibling, who’s confused about when to use C or K.

Feel free to give this lesson about when to use C or K to anyone who might find it helpful.

« Oral Language Supports Early Literacy

53 responses to “When to use c or k”

1. T says: February 7, 2017 at 2:33 am

   Impressive, thank you

   Reply
   • Chandra Sanapala says: December 23, 2020 at 4:32 pm

     Beautiful and simple to grasp.

     Reply
2. Dww says: February 13, 2017 at 5:42 am

   Very helpful. Thanks. I agree with the method – student spots the pattern versus being told the rule.

   Reply
3. A says: May 29, 2017 at 8:04 am

   Thank you. I love the investigation process too.

   Reply
4. Mel says: June 25, 2017 at 11:01 pm

   oh i love this!!

   will use in my class – thank you! It makes so much more sense to allow kids to investigate the rule for themselves rather than just tell them.

   Reply
5. Asha says: August 7, 2017 at 8:04 pm

   Thank you so so much.. God bless

   Reply
6. natasha says: August 26, 2017 at 9:44 pm

   Thank you as a parent I appreciate you posting this. It made helping my daughter so much easier

   Reply
7. Sagar Nagane says: October 23, 2017 at 3:20 pm

   Thank you very much!!!!

   Reply
8. Matthew says: January 8, 2018 at 6:40 pm

   I’ve just come across this while planning a lesson about this exact topic. Thank you very much!

   Reply
9. jennifer says: May 28, 2018 at 3:56 am

   Excellent, very thorough. Thank you.

   Reply
10. Krupa says: June 29, 2018 at 12:18 am

    Thank you so much I am going to save this for future. My son is 4yrs old and he knows sounds and started forming 3 letter words and he gets confused in c k sound, for now i tell cat C and Kite K. Do you have any suggesation how to teach him, as he does not know vovels.

    Reply
    • alison says: July 6, 2018 at 9:09 am

      Dear Krupa, sorry for the delay in replying, I have been snowed under. If you follow any good systematic synthetic phonics program, it will introduce letters then letter combinations in a logical way, but please also remember that your son is only four, so helping him learn oral language via lots of pretend play, stories, games and just chatting is probably the highest priority. Children who start school recognising letters, rhyming and identifying first sounds are in a good position to learn literacy but he doesn’t need to be able to read and spell before he starts school, in some ways that makes the teacher’s job harder as they are having to occupy him while they teach the others things he already knows.

      Reply
11. Rebecca says: July 30, 2018 at 1:21 am

    This is a lovely explanation. Helps one to spell correctly. Thanks for sharing.

    Reply
12. Christine Milton says: August 16, 2018 at 1:57 am

    Wow! Very good practical ideas to foster independence and for children to be able to work out the rule as oppose to you just giving them the rule. I’m all for it. Thank you.

    Reply
13. Rebecca Tomlinson says: October 17, 2018 at 9:27 pm

    Great lesson. Thank you so much for sharing.

    Reply
14. Taruna says: November 20, 2018 at 2:18 am

    Thank you …it is very helpful…I also want to know about how to use c and s letters …like circular…not sircular…. how to explain in easy way

    Reply
    • alison says: November 30, 2018 at 3:52 pm

      Dear Taruna, I’m not sure there is always an easy way to explain when to use c and when to use s, but sometimes these can be linked to meaning to provide a clue e.g. circle, circus, cycle, cyclone are all c and all to do with circles. But sometimes it’s just a case of learning which words have c, and the rest have the standard s. Alison

      Reply
15. Joh says: December 9, 2018 at 11:22 pm

    Why EKG for ECG?

    Reply
16. Vandana Nikam says: January 21, 2019 at 6:05 pm

    Thank you so much…… I love your method to explain the difference. really helpful to all parents, Teachers, and students

    Reply
17. Shannon says: February 1, 2019 at 3:01 am

    Thank you for your explanation. My 5 year old is starting spelling and the 2 words we came across these last 2 weeks are kit and cub. She knows all her letters and is reading already. The question came up when she has to spell the word by sounding it out. It looks in her instance at the beginning of a word if it’s an i, e , or y its a k. and if its an a, o or u its a c. Examples cub, cat, cake, cape, cap, cup, cot, cove, cop, and then kite, kit, kill, keep, key, kilt. Does that sound right? Did think this would come up so early?

    Reply
    • alison says: February 10, 2019 at 5:01 pm

      Hi Shannon, sorry for slow reply, I have been snowed under. Yes, if we put a letter c before e, i or y, the sound is “s” as in cent, city and cycle. We have to use a letter k to spell the sound /k/ before e, i or y, as in Kent, kitty and kybosh. Hope that makes sense. Alison

      Reply
      • Thivya says: July 27, 2020 at 11:41 am

        Hi, Thanks for your c,k,and ck rules… But can you help me to find how c in Word ‘object’ and ck in jacket???

        Reply
        • alison says: July 27, 2020 at 2:03 pm

          Yes, ck is used for syllable-final /k/ sounds in one-syllable words with a “short” vowel like “back”, “neck”, “sick”, “lock”, “duck”, and also in the first syllable of words like “jacket”, “cricket”, “pocket” and “bucket”.

          If the last two sounds of the syllable are /k/ then /t/ we typically use ct, as in “fact”, “sect”, “evict”, “concoct” and “duct”, unless it’s a past tense verb/past participle, in which case we use cked as in “backed”, “wrecked”, “clicked”, “blocked”, “ducked”. Hope that makes sense! Alison

          Reply
18. Shivani Yadav says: April 25, 2019 at 2:47 pm

    Is vedic or vedik which is correct?????

    Reply
    • alison says: May 2, 2019 at 7:55 pm

      Hi Shivani, I have always thought “vedic” but I’m not an expert on this word, so that could be wrong.

      Reply
19. bill says: July 20, 2019 at 6:32 am

    my sister think that taco is spelled with a k and she is in seventh grade im in fith grade and i know that it is spellled with an c not an k so someone please help me and prove my point

    Reply
    • alison says: July 21, 2019 at 9:28 am

      Dear Bill, you know you can use a dictionary to check how words are spelt? Tacos come from Mexico, where they speak Spanish, and Spanish doesn’t use the letter K much. Even in words borrowed from other languages, they often change K to a C. When I lived in Mexico years ago I was surprised to find that the Spanish word for “kangaroo” is “canguro”. Hope your sibling rivalry with your sister resolves into warm and lifelong loving friendship. All the best, Alison

      Reply
20. Riddhi says: November 2, 2019 at 7:26 pm

    Hi I want to know how to explain to my 6 year old when a word begins with kn or n .

    Reply
    • alison says: November 4, 2019 at 4:54 pm

      Hi Riddhi, the spelling kn is used in words from Old English in which the /k/ was pronounced before the /n/. There isn’t a “rule” to tell you which words they are, but the main base words are in this list: http://www.spelfabet.com.au/spelling-lists/sorted-by-sound/n/kn-as-in-know

      Reply
21. Deepa says: February 11, 2020 at 7:32 pm

    This is a gem! Thanks

    Reply
22. Jony Haji says: June 6, 2020 at 5:37 am

    Why does camera pronounced with k instead of s

    Reply
    • alison says: June 8, 2020 at 10:35 pm

      Because the letter C is followed by A in “camera”, not E, I or Y as in “cent”, “city” or “cyclone”

      Reply
23. Pushpa Hawargi says: September 5, 2020 at 1:55 pm

    Thanks

    Reply
24. Sweta says: September 30, 2020 at 9:10 pm

    Then why is Kashmir not written as cashmir and kangaroo not written as cangaroo?

    Reply
    • alison says: October 3, 2020 at 9:56 pm

      Because English has spelling patterns, not hard-and-fast rules. Kashmir is from Sanskrit and kangaroo is an Anglicized version of a Guugu Yimidhirr word, and loan words from other languages tend to stick less closely to the patterns we get from the main base languages of English. Some other words for Australian wildlife (koala, kookaburra, quokka) use K where you’d ordinarily expect a letter C. Sorry about that, it wasn’t my idea.

      Reply
25. Joanne says: October 28, 2020 at 11:45 pm

    Thanks for this great explanation. I am preparing a lesson on ck and k endings. There seem to be lots that have a ck in the middle that are more than 1 syllable. Do you suggest covering those at all? I am thinking of words like chicken, packet, bucket, attack, buckle. Lastly, do you suggest introducing it all in one go with younger kids or just sticking to the ck (after short vowel) and k (after a consonant) and leaving words that just have a c (picnic, music etc ) for later?

    Reply
    • alison says: October 30, 2020 at 2:25 pm

      Hi Joanne, I’d just follow your teaching sequence, some of them do more one-syllable word work before starting on words of more than one syllable, and others bring in two-syllable words early. Whichever way you do it is fine I think, the main thing is to have an established teaching sequence and then stick to it. All the best, Alison.

      Reply
26. Gaelan says: December 10, 2020 at 4:44 am

    why can’t we just have a language that has one symbol per one sound …is it really too much to ask have a logic in spelling, do I really have to learn 250+ different Letter combinations for one sound… let’s just spell how it sounds stop this retarded madness.

    Reply
    • alison says: December 10, 2020 at 10:28 pm

      Because every language gets the orthography it deserves, and English orthography is a very efficient way to represent both sounds and meaningful word parts plus distinguish between homophones, though since it’s generally not taught well it’s poorly understood. If we had one spelling for every sound we would have no “act” in “action”, no “music” in “musician”, no “discuss” in “discussion” and so on, but once you know how it works it’s actually quite an elegant system.

      Reply
27. Helena says: March 7, 2021 at 8:11 pm

    Hello, dear author! Your lesson is helpful and interesting for me. Thank you! And also I have a question, how would you explain why we writing “c” not “k” in “cash”, “car”, etc.

    Reply
    • alison says: March 8, 2021 at 7:53 pm

      We typically write C before back vowels and K before front vowels, and the reasons are complicated and historical, this History of English podcast is about this: https://historyofenglishpodcast.com/2012/07/17/episode-5-centum-satem-and-the-letter-c-2/

      Reply
28. Vidhi says: May 21, 2021 at 11:29 pm

    Why if click or clock with a and not klock or klick?

    Reply
    • alison says: May 23, 2021 at 4:43 pm

      I am not sure I understand the question. We tend to use letter c before a, o and u (back vowels) and before r and l, but k before e, i and y. There are some common exceptions e.g. the name Kate, the word ‘skate’ which comes from Scandinavia, and some of Australia’s fauna e.g. kangaroo, koala, kookaburra. The reasons for this are complicated and I’m not sure I fully understand them yet, but if you’re interested you could start with this History of English Podcast: https://historyofenglishpodcast.com/2012/07/17/episode-5-centum-satem-and-the-letter-c-2. All the best, Alison

      Reply
      • Vidhi says: May 23, 2021 at 7:19 pm

        Yes thank you. You answered to my question and I found it elsewhere too. The consonant blends /cl/ and /cr/ will use c and not k. 🙂 hence it is click and not klick.

        Thank you again.

        Reply
29. Sharmila Bose says: August 26, 2021 at 10:27 pm

    Thank you for the clarification.

    Reply
30. Kristy Genung says: September 29, 2021 at 11:09 am

    Another reason ck isn’t used in words like talc is that the /k/ has to be RIGHT after the short vowel. If there’s another consonant there we can’t add ck because ck can’t be clustered with another consonant.

    Reply
    • alison says: September 29, 2021 at 12:42 pm

      Good point, though there are a tiny few exceptions. I have added a sentence to this post to make that clearer: “It is used after one-letter vowel spellings, with very few exceptions (I can only think of ”hoick’, ‘arcked’, ‘zincked’ and ‘talcked’).” THANKS! Alison 

      Reply
31. Vaishnavi says: October 7, 2021 at 8:54 pm

    Mam could you please tell me the different sounds of gh and how they should be used

    Reply
    • alison says: October 8, 2021 at 12:38 pm

      Have a look at this page on my website: http://www.spelfabet.com.au/spelling-lists/sorted-by-spelling. The spelling gh is listed as a grapheme in its own right, as in the words ‘ghost’ and ‘laugh’, but it’s also part of the spellings ‘aigh’ as in ‘straight’, ‘eigh’ as in ‘eight, height, Leigh’, ‘igh’ as in ‘night’, ‘ough’ as in ‘bought, dough, drought, through, thorough’ and ‘augh’ as in ‘caught’. It mostly represented a sound we don’t say any more in Old English (a voiced /h/ type sound), and the spelling was retained after it stopped being pronounced, or shifted forward in the mouth to become /f/.

      Reply
32. Sharon says: July 28, 2022 at 4:18 am

    I heard a person on Tictok say she had her kids draw a C and turn it into a cat by using lc a for eyes, lc o for a nose and lc u for a mouth then closing it up and giving it whiskers. She then drew a K and turned it into a kite by adding lines to the right side to form a diamond putting a lc t in the center from too to bottom and adding a I on the lower left of the center lines and an e on the lower right side. Which btw would spell kite of course, but it should the kids if ot has a.o, or u it would follow a c and I, or e would follow a k.

    Reply
    • alison says: July 28, 2022 at 6:38 pm

      Nice one! Alison

      Reply
33. ganesh says: May 15, 2025 at 1:17 am

    why we cant write bak instead of back lack instead of lak

    why we need c with k? To protect from long vowel , we could double K for example bak-bakking, lak-lakking

    Reply
    • alison says: May 15, 2025 at 11:18 am

      I didn’t make the system up, I’m just trying to help people understand it!

      Reply

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