How to know if something’s a duck:
1. Ask yourself if something’s a duck.
a. If the answer is yes, then you are done. Feed it something. It’s hungry, you dick.
b. If you are unsure, please see #2.
c. If the answer is no, then you are done. It’s probably an alien. From the movie Signs, starring Mel Gibson.
2. Take a nap, have a wet dream about Angela Lansbury, then kindly redo #1.