The absolute best strategy you can teach your students is to recognize vocabulary from context. English speakers are so wordy, so redundant, and constantly adding paraphrases and examples that students can easily understand a speaker without understanding all the words.
A group of Japanese I am teaching went on a field trip to learn about business. This one was amazing. It's a business incubator in downtown St. Louis, called T-Rex. It rents space to start up businesses. Anyway, I took notes on the lectures and typed them up for students to analyze and guess the meanings of words in bold type. Here are three of them.
1. They need revenue, or money. 2. You have to farm out what you don't want to do, hire others to do this work. 3. It's important for your business to stand out, look different from your competitors. You'd think it would be easy for my students to figure out the meanings with such blatant paraphrases. Not necessarily. I had them do the exercises for homework and go over the answers in groups. Then, I called on them for answers. I find it very difficult to get Japanese students to speak aloud in class. Sometimes I offer mini candy bars to those who dare to ask questions and most won't. Anyway, if they recognize the explicitness in our language, this will help build their vocabulary and listening comprehension. There simply isn't time to rush to a dictionary. Also, next week, this group will be presenting ideas and paraphrasing will make their ideas clear to the audience. Any non-native who presents in the fashion that native speakers do, with topic sentences, transitions, and redundancy, will have little trouble communicating despite difficulties with pronunciation.