The case of u is similar to that of i in English. There are two main types of [u] sound: /uː/, which is long and high, and /ʊ/, which is short and a bit more open. And then there is a third one, /u/, which is a mixture of the previous two.
Let’s listen to the following examples:
Blue book. /bluː/ /bʊk/
It took root. /tʊk/ /ruːt/
I could do it soon. /kʊd/ /du/ /suːn/
Look at your wounds and bruises. /lʊk/ /wuːndz/ /bruːzɪz/
Wolves howl at the full moon. /wʊlvz/ /fʊl/ /muːn/
Now, let’s have a look at them one by one.
uː This is like a Spanish [u] in quality. The tongue is raised high at the back of the mouth and the lips are closely rounded. It is a very long sound.
- How to do it? Say an u as you do in Spanish, but keep it much longer. Check that your lips are forward and rounded and your tongue at the back of your mouth.
- Spelling. The main realizations are u (flute, rule) and oo (tool, spoon). Also it frequently occurs as o (do, who), ou (wound, through), ew (flew), ue (blue), ui (suit) and oe (shoe).
ʊ This is a short sound, which stands in between /uː/ and /ə/ in quality. The lips are rounded but in a loosely way. There is more relaxation in the tongue and lips than in /uː/.
- How to do it? Say an /ə/ -that is, the schwa- with your lips rounded and it will come out as /ʊ/.
- Spelling. It is mainly found as u (put, full, butcher) and oo (took, book, look). Also as o (woman) and ou (could).
u It has the quality of /uː/ and the length of /ʊ/ (short). It only occurs in unstressed syllables. It is exactly like the Spanish u. This sound is usually left out of the vowel chart. If you want to know why, click here.
- How to do it? Like /uː/ but short. Just as you do an u in Spanish.
- Spelling. It is found as u in the middle of words (situation). In unstressed words is mainly found as o or ou (Do I have…, to us, looking at you).
To remember: There is a clear parallel between the group /uː/, /ʊ/ and /u/ and the group /iː/, /ɪ/ and /i/. The three sounds included in each group hold the same kinds of relationships among themselves.
- Both /ʊ/ and /ɪ/ are short and stand midway in quality between the long vowels /uː/ and /i:/ and the schwa, /ə/.
- In both groups there is a third, mixed sound, /u/ and /i/, respectively, which is not a phoneme and only appears in unstressed position.
This similarity can help you remember its characteristics and produce them correctly.
Now, let’s listen to some speakers:
You say, that is a wolfish man (A.S. Byatt, BBC4). /ˈwʊlfɪʃ/
These are dark, doomy, gloomy places where bad things happen in the corners (Briony Hanson, BBC4). /ˈduːmi/ /ˈɡluːmi/
It was a complete fluke that I said that I wanted to be involved with the film at all (Keira Knightley, BBC4). /fluːk/
Our warning is what could. And this is what could happen (Michael Caine, BBC4). /kʊd/
He greets ticket collectors and stationmasters and they return his salute (Julian Barnes, KUSP). /səˈluːt/
Very fulfilled as a woman (Ben Kingsley, BBC4) /fʊlˈfɪld/ /ˈwʊmən/
And also see how close to a schwa the phoneme /ʊ/ can be in American English:
We all wanted to do something very authentic to her book and to be very respectful of the book (Julia Roberts, BBC4). /bʊk/