A clear accent - and a good speaking voice in any language -requires you to open your mouth in order to form the words properly.

It sounds obvious, yet how many times have you heard someone mumbling nervously through an interview, or speaking to quickly in a corporate presentation?

Speakers with, for example some Indian accents and some regional British accents (Glasgow and Liverpool in particular) don't tend to open their mouths very wide when they speak.

For non-native speakers of English, what this means is that when you DO speak English, you are literally not opening your mouth wide enough to make the sounds and speak the language properly! Some of the long English vowel sounds such as the 'aw' in 'prawn' and the 'oh' in 'phone', both of which need an open mouth for correct pronunciation, are shortened to an 'o' sound....which is not correct for a clear, neutral British accent.

So, what can you do?

The main thing is to practice opening your mouth wider than you would normally when you are speaking English. Yes, it will feel a little strange, but you will find that by moving your mouth more, your are able to pronounce English words clearly and with a better accent.

The is a particularly important for the correct pronunciation of English vowel sounds, which non native speakers, as I have mentioned, often pronounce incorrectly by not keeping their mouths open enough, or by putting their mouths in the wrong position.

How much does this matter? Well how well do you want to speak English?! The important point is that a strong accent can be difficult to understand, and if you are difficult to understand, people will just stop listening.

One of the most useful things you can do is practice vocal exercises to improve your pronunciation. The following exercise encourages you to practice English vowel and consonant sounds without forming them into words, and it's one that I often use in accent reduction and public speaking classes:

The sounds are:

Oo as in shoe
Oh as in phone
Or as in port
Ah as in cart
Ay as in pay
Ee as in sheet

As you can see, these are all long English vowel sounds, so stretch them out to make sure that you aren't shortening them.

Of course, it's difficult, if not impossible to imagine the sounds of English from the written word, so listen for these sounds as spoken by native speakers, and copy them.

Improving your English is often about changing mother tongue habits and opening your mouth a little wider when speaking English is one of them.

Annabelle is the author of "Confident English - improve your spoken English...today!" at http://www.coachmeconfident.com and a professional communication skills trainer and accent reduction coach.