If you learn enough German but then need to write or speak in English, you may often be tempted to use the following words (at least, in my case):
trainer. It looks like a perfect English word, except that it will confuse people. What is usually meant is actually coach.
mother language, because the German word is
die Müttersprache die Muttersprache, but it should be either native language or mother tongue.
I read a roman, and yet difficult to catch because Roman is likely something or someone from Rome. It should be then a novel.
make a picture while the word make here should be take instead.