Go through signs and notices - do the quiz:
http://www.helpforenglish.cz/article/2014010601-signs-and-notices-photo-quiz-10
http://www.helpforenglish.cz/article/2012070401-signs-and-notices-photo-quiz-9
http://www.helpforenglish.cz/article/2012031401-signs-and-notices-photo-quiz-8