Pronunciation involves far more than individual sounds. Word stress, sentence stress, intonation, and word linking all influence the sound of spoken English, not to mention the way we often slur words and phrases together in casual speech. 'What are you going to do?' becomes 'Whaddaya gonna do?' English pronunciation involves too many complexities for learners to strive for a complete elimination of accent, but improving pronunciation will boost self esteem, facilitate communication, and possibly lead to a better job or a least more respect in the workplace. Effective communication is of greatest importance, so choose first to work on problems that significantly hinder communication and let the rest go. Remember that your students also need to learn strategies for dealing with misunderstandings, since native pronunciation is for most an unrealistic goal.
A student's first language often interferes with English pronunciation. For example, /p/ is aspirated in English but not in Spanish, so when a Spanish speaker pronounces 'pig' without a puff of air on the /p/, an American may hear 'big' instead. Sometimes the students will be able to identify specific problem sounds and sometimes they won't. You can ask them for suggestions, but you will also need to observe them over time and make note of problem sounds. Another challenge resulting from differences in the first language is the inability to hear certain English sounds that the native language does not contain. Often these are vowels, as in 'ship' and 'sheep,' which many learners cannot distinguish. The Japanese are known for confusing /r/ and /l/, as their language contains neither of these but instead has one sound somewhere between the two. For problems such as these, listening is crucial because students can't produce a sound they can't hear. Descriptions of the sound and mouth position can help students increase their awareness of subtle sound differences.
Here are some ideas for focusing on specific pronunciation features.
Voicing;
Voiced sounds will make the throat vibrate. For example, /g/ is a voiced sound while /k/ is not, even though the mouth is in the same position for both sounds. Have your students touch their throats while pronouncing voiced and voiceless sounds. They should feel vibration with the voiced sounds only.
Aspiration;
Aspiration refers to a puff of air when a sound is produced. Many languages have far fewer aspirated sounds than English, and students may have trouble hearing the aspiration. The English /p/, /t/, /k/, and /ch/ are some of the more commonly aspirated sounds. Although these are not always aspirated, at the beginning of a word they usually are. To illustrate aspiration, have your students hold up a piece of facial tissue a few inches away from their mouths and push it with a puff of air while pronouncing a word containing the target sound.
Mouth Position; Draw simple diagrams of tongue and lip positions. Make sure all students can clearly see your mouth while you model sounds. Have students use a mirror to see their mouth, lips, and tongue while they imitate you.
Intonation;
Word or sentence intonation can be mimicked with a kazoo, or alternatively by humming. This will take the students' attention off of the meaning of a word or sentence and help them focus on the intonation.
Linking;
We pronounce phrases and even whole sentences as one smooth sound instead of a series of separate words. 'Will Amy go away,' is rendered 'Willaymeegowaway.' To help learners’ link words, try starting at the end of a sentence and have them repeat a phrase, adding more of the sentence as they can master it. For example, 'gowaway,' then 'aymeegowaway,' and finally 'Willaymeegowaway' without any pauses between words.
Vowel Length: You can demonstrate varying vowel lengths within a word by stretching rubber bands on the longer vowels and letting them contract on shorter ones. Then let the students try it. For example, the word 'fifteen' would have the rubber band stretched for the 'ee' vowel, but the word 'fifty' would not have the band stretched because both of its vowels are spoken quickly.
Syllables;
Have students count syllables in a word and hold up the correct number of fingers, or place objects on table to represent each syllable.
Illustrate syllable stress by clapping softly and loudly corresponding to the syllables of a word. For example, the word 'beautiful' would be loud-soft-soft. Practice with short lists of words with the same syllabic stress pattern ('beautiful,' 'telephone,' 'Florida') and then see if your learners can list other words with that pattern.
Specific Sounds;
Minimal pairs, or words such as 'bit/bat' that differ by only one sound, are useful for helping students distinguish similar sounds. They can be used to illustrate voicing ('curl/girl') or commonly confused sounds ('play/pray'). Remember that it's the sound and not the spelling you are focusing on.
Tongue twisters are useful for practicing specific target sounds, plus they're fun. Make sure the vocabulary isn't too difficult.
The Sounds of English, American Accent Training, and EnglishClub.com websites below offer guidelines for describing how to produce various English sounds. You can find representative practice words for every English sound on the English is Soup site.
Here are some resources for teaching pronunciation.
Sounds of English
Mouth diagrams and photographs; instructions for producing selected English sounds, word stress, sentence stress, and intonation; many example sound clips to play with audio software such as RealPlayer (free).
American Accent Training: Pronunciation
The most common trouble sounds in English and how to pronounce them.
EnglishClub.com English Pronunciation - Pronunciation for ESL learners;
Guides to word and sentence stress, linking, pronunciation of '-ed' and 'the,' and other topics.
Some Techniques for Teaching Pronunciation
Detailed - instructions for two pronunciation activities.
English is Soup: A Phonics Resource For ESL - Adults
Mouth diagrams and representative words showing various spellings for every English sound; short introduction to rules of pronunciation based on spelling; PDF format.
The Tongue Twister Database
Large collection of tongue twisters to practice specific sounds.
Source: http://writing.colostate.edu/guides/teaching/esl/pronunciation.cfm
Source: http://writing.colostate.edu/guides/teaching/esl/pronunciation.cfm