c) Uso de diccionarios para mejorar la pronunciación.

How to improve your English pronunciation using a dictionary?

There are several ways to improve your pronunciation skills. One of the easiest is to invest in a good dictionary.

You don’t have to find a native speaker to learn the pronunciation of an English word. You just need to look it up in a dictionary. Most dictionaries will show you the phonetic pronunciation of words. To find out the pronunciation, look at the phonetic transcription given next to the word in the dictionary. In the online dictionaries such as Cambridge, Oxford, and Longman etc. you can interact with them in order to listen and interpret the phonetic transcriptions of words. 

http://dictionary.cambridge.org/dictionary/learner-english/pronunciation?q=Pronunciation