It's a good book if you are lacking English grammar knowledge. If you can't understand the rules for grammar of your own language, you are not going to find it easy to do so in another language.
German=Better English
In Swiss German "schaffen" = arbeiten= working. So if you use it in this way the past participle would be "geschafft"
For excample: I've been working all day long = Ich habe den ganzen Tag geschafft (g'schafft)
Read this thread. A lot of language schools have been discussed here.
[[German] Which is the best school in Zurich?](http://www.englishforum.ch/language-corner/3147-german-best-school-zurich.html)
I work mainly with Swiss colleagues, so the English I speak around them is not the sort of English I would speak back in my home country. It's not quite a "dumbed down" English, but it's a very basic, no frills English. I do this mainly because I've been told by many Swiss people that they don't like it when native English speakers speak very fast and fill their speech with metaphors, flowery descriptions and sayings that are not familiar in the German language.
Though, put me in a room full of native English speakers, and I'm sure it will all come rolling back!
One often hears "Who did you meet?". After learning German, the more correct "Who m did you meet" sounds logical.
Another example: "It is I" is hopelessly pedantic. Everyone says "It is me".