an
Notice that an is used instead of a before words that start with a vowel sound, such as incredible.
more information: a & an
advice
Follow the link for some advice about the word advice and advise.
more information: advise & advice
felt
Here felt is the past tense of the irregular verb feel. Follow the link to listen to some examples.
more information: feel
in touch
To be in touch is to communicate with or contact someone.
Example: We'll be in touch.