Riddle: Coffee can go in, but tea cannot.
Riddles can go in, but questions cannot.
Quizzes can go in, but surveys cannot.
Spoons can go in, but forks cannot.
Green can go in, but red cannot.
Glass can go in, but plastic cannot.
Doors can go in, but windows cannot.
Why can some go through the green glass door and others can not?
Answer: Green Glass Door all have double letters. Therefore, only the words with double letters can pass through the Green Glass Door!