To find a word's definition, teachers and students can look in any number of definition-based dictionaries. In addition, there are bilingual dictionaries that provide translations, and picture dictionaries that supply pictures. Bilingual electronic dictionaries exist that will not only provide a translation, but pronounce the word and save it for download to a computer later. Using such resources, students can look a word up and find a definition, translation, or picture, and even hear the word pronounced.
To find a word's collocates, teachers can look in dictionaries of collocations such as the LTP Dictionary of Selected Collocations (Hill and Lewis), or the Oxford Collocations Dictionary (2002). And this is a very good thing, because we are simply not very good at coming up with a word's collocates off the top of our heads (Fox).