In English we use sounds which you might not use in your language so these sounds might be difficult for you to produce. For example, the /f/ sound.
Your mouth has many muscles which you use to produce sounds with your teeth, tongue and lips.
Here are some tips to practise difficult sounds:
1) Find out what the mouth does when producing the sound. Ask your teacher or watch the videos on the BBC website.
2) Use a mirror and practise moving your mouth / lips / tongue / teeth in the correct way. E.g. for the /f/ sound, touch your top teeth on your bottom lip and push air through the gap. There is no voice from the throat and when you say this sound you can feel the air on your hand when you put it in front of your mouth. This may feel strange but the more you practise, the easier it will become. Your mouth should ache in the same way your body does after you do exercise!
3) Make a list of words which contain the difficult sounds. Make sure this list contains a variety of words with the sound at the beginning, middle or end. E.g. for the /f/ sound:
4) Practise saying these words and focus on the problem sound. Look in the mirror to check that your mouth is moving in the correct way.
5) Put the words in a sentence and practise saying the sentence. It is more difficult to produce the sound when it comes in a sentence.
Remember, when you’re speaking English, if you make a grammar mistake, people can still usually understand you, but if you have problems with pronunciation, people may find it difficult to understand you. Good pronunciation is the key to good communication!