Here is a little something on the sound /ng/. I wrote it for my students at a
Teacher Training College. Enjoy it. Comments are welcome, esp. regarding
the length and quality of the text, the level of difficulty and the "do-ability" of the exercise
If anybody is interested I also have a recording of the text.

D i a l o g u e
In the following dialogue most words with /ng/ are not followed by /g/ or /k/. There are a few words, however, where /g/ or /k/ appear after /ng/. As you listen to the dialogue, find such places, and highlight them. Then repeat the conversation with a partner.

The Meeting
Mr. Manning : Mrs. Lang, is anything wrong? What's this moaning and groaning all about?
Mrs. Lang: Well, Mr. Manning, the teachers are complaining about having to attend the
Mr. Manning : I know that sitting in a meeting and discussing our recruiting and grading
policies isn't half as exciting as watching horse racing on TV. The thing is
though, participating in our weekly gatherings is directly linked with
what we're earning. Well then, Mrs. Lang, who's not coming?
Mrs. Lang: Well, Mr. Wang Tang says he's having his ping pong training in the evening.
Mr. Manning : What about the young Keating?
Mrs. Lang: Mr. Keating is taking his driving test.
Mr. Manning : I think Keating's lying. I just saw him carrying his angling rod. What about the
Sterlings? Are they planning to spend the evening quarreling again?
Mrs. Lang: Well, they haven't been getting along recently. They're getting divorced.
They're waiting for the ruling regarding their siblings.
Mr. Manning : And Frank King?
Mrs. Lang: Mr. King is having his wedding ring removed. It has to do with the swelling on
his finger. It's getting pinker and pinker.
Mr. Manning : Mrs. Lang, what're these... things hanging from your shoulder ?
Mrs. Lang: These are wings.
Mr. Manning : Wings? Are you joking, Mrs. Lang?
Mrs. Lang: I'm being dead serious, Mr. Manning.
Mr. Manning : Are you... flying anywhere?
Mrs. Lang: Well, I think I might say so. I'm flying to Beijing.
Mr. Manning : Flying to Beijing? Mrs. Lang, am I dreaming or is this really happening ?
Mrs. Lang: Beijing, Mr. Manning, is the new bingo hall they are opening this evening. I'm
performing in The Kings of Swing. The wings are just a prop.
Mr. Manning : Performing? You mean like singing, dancing, and fooling around?
Mrs. Lang: Among others, Mr. Manning. I thought I'd bring the wings to get used to
wearing them.
Mr. Manning : Well then, since nobody's coming to the meeting there's no point in
organizing it. You know what, Mrs. Lang? I think that instead of getting angry
I'll just get around to cleaning my car. Frankly speaking, I love polishing my
Mustang while listening to Sting, the Rolling Stones or Bing Crosby.
Mrs. Lang: Mr. Manning, your Mustang can wait. I suggest spending the evening
in "Beijing".
Mr. Manning : (to himself) An evening playing bingo and watching Mrs. Lang singing and
dancing in The Kings of Swing, wearing her flying wings and those dangling
earings. I'd rather sink in a sea of some stinking ink than listen to this
twang, twang, twang.
Mrs. Lang: Did you say something, Mr. Manning?
Mr. Manning : Oh, nothing.
That is quite a tongue-twister! I should think your students enjoy it.
Indeed a complex test. Perhaps someone could put up a few basic rules on /ng/ pronunciation? When do we say /g/ and when does it disappear?
Students: Are you brave enough to let our tutors analyse your pronunciation?
You will always be correct if you pronounce the g.

It does get missed off sometimes - 'hangin' movin' etc, but this is really as case of accent/dialect and is considered a bit sloppy. Or it is done as a means of sounding 'street-cred', but you will find it simpler and more natural sounding to stick with the g.
Hi, Nona!
I agree that you'd always be correct if you pronounce the "g". But I don't think not pronouncing it is considered sloppy. It even sounds more natural to me. Emotion: smile
I don't necessarily agree that you always pronounce the g. You always pronounce the "ng" sound, and then it's a matter of whether or not you add a "g" or "k" after it, depending on the word.
Students: We have free audio pronunciation exercises.
The ng and g or nk and k sounds are not separate so I don't understand what you mean.

And, when I say it is sloppy to drop the end sound of 'g', I still think that is true, but it is a vice we are almost all guilty of, myself included! But for a non-native speaker it is easy to make this sound 'forced' so I think it best to stick to sounding the g.