Careful and attentive teachers act as role-models for the proper pronunciation of sounds of the English language.
They speak clearly and purposefully. They monitor their speed, and modulate their voices. And they distinguish between different sounds. Also, a successful teacher who is familiar with the students, can effectively engage them, and offer them satisfaction.
Emphasizing the repetition of rhythmic expressions of English, in context, is essential. This also helps in reinforcing grammatical structures, used in various situations.
Repetitive training guides the student to produce the desired sound.