To be grateful is to be happy and grateful for what you have. When you are grateful, you are usually more positive and happier.
When something bad happens to you, it's called misfortune. Misfortune can be anything from getting a bad grade to getting involved in a car accident.
Drinkable means that something is safe to drink. You can drink a drinkable paint, for example, without worrying about the chemicals that are in it.
To revolutionize something is to change it completely. When the government starts to revolutionize, they are changing the way that the country is run.
Mushroomed is an adjective that is used to describe something that has grown in a strange or unexpected way. When you say that something has mushroomed, you are describing it in terms of how it has changed or grown.