I don't use my French or Spanish day-to-day but in my export job I often find myself explaining quite technical matters to people whose first language is not English. Luckily I love writing and I enjoy word-processing so writing an email can be quite a lengthy process where I re-write and edit so as to make my email as clear as possible. When I see some of my colleagues' efforts I feel embarrassed - I once saw a fax my boss had written to somebody in Turkey in his usual pompous, florid language and she had found it necessary to get a dictionary and write the translations of some of his words on the paper, which is unforgiveable.
What I love about word-processing is that you can make a small change and alter the entire meaning of the sentence. The first version ceases to exist and a completely new version appears which uses the same number of words, or fewer if possible, but says exactly the same thing, much more clearly and succinctly.
I also tend to speak in a much clearer, less idiomatic English when talking with my overseas customers.