One of the frustrations in learning French is often that you're not given the words you really need to know. I learnt French up to A-level, but I was utterly at a loss when I lived in France and went out with my French girlfriend and a few of her friends. I was feeling suitably smug about following the whole conversation in French - until everyone started talking about 'chestnuts'. At the end of almost every story, someone would mention them. Now, it's not often chestnuts crop up in most conversations (!), so I thought I'd check with Isabelle later on. When I asked her about it, she said her friends hadn't been talking about chestnuts at all. When I pressed her, she said they hadn't been saying 'marrons' but 'marrant', which is slang for 'funny'! The next day, I started a list of all the slang words - or 'argot' - I came across, and within a few weeks I had over a hundred.

This is just a trivial example of what anyone knows who has lived and spoken French among French people: the words they use are often not what you learn in Longmans Audiovisual French! More often than not, they are 'argotique' or slang. For example, a house is not a 'maison' but a 'baraque'; a car is not a 'voiture' but a 'caisse' or a 'bagnole'. Similarly, pupils spend a long time being taught vocabulary for a given set of situations and environments - doing the shopping, going to school, going to the cinema etc - but they are rarely given a simple list of the most common words. You can easily find a list of the 2,000 most common words in French (http://en.wiktionary.org/wiki/Wiktionary:French_frequency_lists/1-2000), and learning those words would probably be much more useful than learning 'le muguet' (or lily-of-the-valley), which I remember cropping up in my own Longmans text book!