This text below is taken from the updated and expanded 2005 version of Conference Interpreting – A Students’ Companion by Andrew Gillies (see bibliography) and suggests some strategies for acquiring language at advanced level. It is reproduced with kind permission of Tertium, Cracow.
These two exercises are probably the single most rapid and effective way of expanding your active language skills that you will find. All you need is a little application.
3.5 Learn by heart, and practise reciting, 5-10 lines of well written text in your B language every day. Each day check that you still know all the previous days’ texts each day. This may sound ambitious but it won’t actually take more than 10 minutes and after a week you will find yourself using the new structures and expressions when you speak your B language.
This exercise will contribute very quickly and effectively to expanding the active vocabulary of your B language by moving not only words but also entire structures instantaneously from your passive to your active knowledge of a language.[1]In a short time you will have large body of good quality language that can be recalled instantaneously.
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3.7 Learn off-by-heart and mimic 2 minute extracts from, interviews, speeches and stand-up comedians in your B language. Copy the speaker’s sentence intonation as well as pronunciation. Learn one per day and each day check that you still know all the previous days’ texts.
This exercise will help you develop the correct sentence intonation and rhythm when speaking your B language. Both are very difficult to learn and often give away foreign speakers of English who otherwise have a very good cammand of the language.
In addition learning extracts by heart will function as in 3.5, moving words, structures and here also intonation patterns directly from passive to active language knowledge.
(Comedians are mentioned here because to sound really authentic you will have to feel like you are exaggerating the accent when you speak….but in fact it will not be as over the top as you think.)