What is the difference between /tr/ & /tʃ/?



I'm very confused!

A youtube video explained /tr/ should be pronounced like /tʃr/. See https://www.youtube.com/watch?v=DNHI1biK0-4.

Another youtube video explained /tr/ should be pronounced like /t/ & /r/ and try to make a quick link between 2. https://www.youtube.com/watch?v=kMAv3B5xMZc.

So which one is correct?

/TR/ is the most difficult sound I have ever known. In other words, how can I distinguish between "cheese" & "trees"; "choose" & "true"?


Posted 2015-01-19T08:59:56.943

Reputation: 9 656

I would say the second video is better for British English, the tʃr sound being quite hard to pronounce, for me at least. – None – 2015-01-19T09:11:01.230

The difference is simple: one has a rhotic and the other does not. If you are having trouble, you are probably not pronouncing the r correctly, but you might also have the wrong placement of the initial t, and the combination of the two won't work for you because one or both are wrong. As the linked duplicate explains, pronounce trees as [t͡ʂɻʷiz] and cheese as [t͡ʃiz]. That's all there is to it. You may need more of a rounded, retroflex rhotic than you are attempting. It should not normally sound like [t̪ɾiz] as an Italian or Spaniard might say it, although a few speakers may do so. – tchrist – 2015-01-19T13:56:40.217

If you can say 'rue' without any problems, try saying 'chrue'. Don't make it too long - not 'chuh-rue'. Start as if saying 'cheese' then quickly jump in with 'rue'. That's near enough the sound. You could sharpen it with a 't' sound with practice. – Mynamite – 2015-01-19T14:05:02.403

2They're *both* correct. Some dialects use /tr/ and some use /tʃr/. Americans won't notice the difference (unless for some reason they're listening for it). – Peter Shor – 2015-01-19T15:35:13.290

@PeterShor But if you listen to the "Australian" one, when she does it slowly, you get /t/ and then /r/. But as soon as she runs them together you get the apico affricate as usual! They aren't different! You can listen from around 6.25 in... :) – Araucaria - Not here any more. – 2015-01-20T15:46:24.177

Ok, so /t/ in most English accents is aspirated. What this means is that before a vowel we get a short period after the /t/ before the vocal fold start vibrating. This means there's a gap before the vowel kicks in and we can hear air rushing out of the vocal tract. Now in front of vowel-like consonants such as /w,r,l,j/ there is still a delay before the vocal folds kick in and we can hear a devoiced version of these consonants. What we hear is the air rushing past the obstruction and out of the mouth. In the sequence /tr/ the /t/ gets pulled back so that we can make the /r/. As the air ... – Araucaria - Not here any more. – 2015-01-20T15:55:50.153

... from /t/ gets released it hisses past the tip of the tongue which is curled up behind the alveolar ridge for the /r/. After a delay there the voicing may kick in and we will hear a properly voived /r/ for a short peiod. Now this articulation is very similar to what happens with /tʃ/. That affricate starts with the tongue pulled back to post alveolar position. The air trapped behind the blockage then hisses out of the gap left by pulling the tip of the tongue down. The difference between the two is mostly discernible just because the voicing kicks in for the real /r/ in the /tr/ sequence .. – Araucaria - Not here any more. – 2015-01-20T16:00:34.967

... in the first video they get you to achieve the affect by starting with /tʃ/ and adding /r/ to it afterwards. If you watch the second video to the end they just get you to do the /t/ and /r/ in close succession. But if you listen to the speaker after 6 mins or so, you will hear the same hissing /tʃ/-like sequence. Both videos are quite bad, but the first is arguably better, because it will get you to start the sound with your tongue pulled back for the /tʃ/. The second is not so good, because you cannot actually start a /tr/ sequence from the normal /t/ position! Hope this helps! – Araucaria - Not here any more. – 2015-01-20T16:05:24.143



There appear to be two separate questions:

  1. Which one is correct?
  2. How can I distinguish between them?

Both pronunciations are correct, but they each represent a different accent. The American pronunciation is /tʃɹ/, as in the first video. The second video features an Australian speaker, thus the pure /tr/ sound.

Assuming you are not a native speaker of English, it seems silly to provide a phonetic analysis of the two pronunciations. My recommendation is to practice the words exactly as taught in the videos. I think they both do a good job, but you need to choose the specific accent you wish to acquire and practice with that video ONLY.

The American accent video does a very good job of teaching awareness of the feel of your lips and tongue so that you include the /ɹ/ sound after the /tʃ/ sound. Here is a bookmark of that portion of the video.

Good luck!


Posted 2015-01-19T08:59:56.943

Reputation: 21

Just a note: not all Americans use /tʃɹ/ (although a lot of them do). But if you say /tɹ/, it won't make you sound like a foreigner to Americans. – Peter Shor – 2015-01-19T23:38:25.967

Sure, but I think it is still fair to label it as the American pronunciation in order to distinguish it from those accents of the various commonwealths. – None – 2015-01-19T23:42:53.463

1There are American adults who don't produce a retroflex affricate (i.e, "Snow Chooper" from Star Wars), but they and their children often go through a stage where initial TR and CH are confused. Since they're indistinguishable for most American English speakers (no matter what they always say, or think they always say), lots of people stick there and never associate the pronunciation with the spelling, if they learn to read. – John Lawler – 2015-01-20T00:15:41.633

@JohnLawler Does this same person pronounces tree as 'chee'? Do you speak of an identifiable regional accent or are you speaking of ESL speakers (e.g. mainland Mandarin Chinese speakers)? I've not encountered an American-born speaker who drops the /r/ from this affricate, whether retroflex or not. I'm not doubting you, I simply lack the personal experience. – None – 2015-01-20T00:33:30.313

@Clumsy I have never heard any native speaker lose the /r/ phoneme there, however it should happen to manifest. – tchrist – 2015-01-20T01:13:47.050


When I pronounce "TR", my lips are "out" and formed as if I'm about to kiss someone. But when I pronounce "CH" slowly, my lips are in a "smiling" position. This is why sometimes the photographer asks the people being photographed to say "cheese".

There are exceptions to the rule. One exception is the "choo choo" onomatopoeia for the train horn. I pronounce it with my lips "out", with the same sound as the word "true".


Posted 2015-01-19T08:59:56.943


1I think the mouth shape depends on the vowel. That's why it's different for chee and choo. But it's also different for tree and true. – Barmar – 2015-01-19T12:41:06.433

@Barmar Absolutely right. The lips will start rounding for the /u/. For some speakers,the lips will starts rounding (we get 'labialisation') for the /r/ as well, so we might get rounding during the initial consonant during "tree", but we nearly always get it for the first segment in "true" because of the /u/ vowel (unless that speaker doesn't normally round their/u/!) – Araucaria - Not here any more. – 2015-01-19T13:29:17.317

The reason that we say "cheese" during photos is because the /i:/ vowel there is pronounced with spread lips. However if we said "chew" the /u:/ vowel will cause our lips to round during the /tr/ segment in anticipation of the following sound :-) – Araucaria - Not here any more. – 2015-01-19T13:40:46.807

I've never understood this saying 'cheese' for photos - I don't look like I'm smiling when I say cheese. – Mynamite – 2015-01-19T13:55:21.503

The lip movements are very similar but with tr woods the action is more with a outward thrust of the top lip whereas ch words have an upthrust of the bottom lip. Well, that's how it works for me anyway! – Mynamite – 2015-01-19T13:58:33.760

Choo and true do not have the same initial consonant. – Janus Bahs Jacquet – 2015-01-19T21:15:42.223

@Janus Not arguing, but American youngsters often need convincing of that, since tree, treat, trade, true seem like chree, chreat, chrade, chrue to a lot of them. Not affricating those seems as fussy as not doing so with did you: it requires t-raining and conscious effort to avoid especially now that elocution lessons no longer involve corporal punishment. :) – tchrist – 2015-01-19T23:22:29.417

@tchrist Not affricating isn't even an option to me, but the two have different affricates. And dropping the /r/ altogether in true (as the last paragraph in this answer says, or at least seems to say) is definitely not an option to me. – Janus Bahs Jacquet – 2015-01-19T23:43:04.043


The difference is the position of the tongue:

Compared to /t/, where the tongue touches the ridge behind the teeth, in /ʃ/ the tongue is just off that ridge and the air almost whistles through it.

For /ɹ/, the tongue is further away and further back, possibly even curled back slightly.

The reason "trees" might sound like "cheese" is that going from the sound of the /t/ through to the /ɹ/ the tongue more or less moves though the same position it would while making /ʃ/. That's why it can sound like /tʃr/.


Posted 2015-01-19T08:59:56.943

Reputation: 274

/r/ is unvoiced after unvoiced plosives in English, unless exaggerated, so there is no difference in voicing (a better term than vocalisation, which more commonly describes the process underlying L-vocalisation). Also please don’t use code text for IPA; that’s not what it’s for—and even worse, the code font used here (Menlo) has horrible spacing problems with diacritics, so your IPA often ends up looking like this: [t͡ʂɻʷiːz].

– Janus Bahs Jacquet – 2015-01-19T21:14:04.717

Ah, good point - thanks - I hadn't noticed the voicing didn't start until the vowel after the /tr/. – user52889 – 2015-01-19T21:34:52.910