1. It means very hungry, starving, or ravenous. （大家可以在作文中尝试同一件事物用不同的词汇来表达，让文章看起来更丰富多彩~）
2. Because when you go to the supermarket hungry, the food you are drawn to is high-calorie junk food, You assign way too much value to calories and so way too little to health and other things.
3. No, because If you miss meals, you tend to gain weight because you get hungrier and eat calorically dense foods.