Today I had a time to talk with Mr. J. J. explaind the word "light" to me. It has a several meaning.. 1. bright 2. electricity 3. not heavy 4. small amount 5. etc. And he gave an example of the forth meaning. I had a light lunch. So I asked him for the situation. If I had a bag of pop-corn without other things, Don't I say "I had a light lunch". He said with a perplexed look "light is a funny english".